Brake Bleeding on an ABS system

Remember the old days when you could rip off a caliper, install a new one, and just bleed the brakes? Well, if you have a vehicle with ABS brake you could be setting yourself up for a trip to the shop after doing that.

ABS systems are VERY sensitive to air bubbles. You know that air rises in the system. Once a bubble gets into the ABS valves, it's almost impossible to suck it back down even with a hand-held vacuum pump. It's definately impossible to do it just by pumping the brake pedal.

There are only two methods left: The first is to use one of the pricey brake bleeding tools that literally pumps brake fluid backwards through the system to force the air bubble into the
brake fluid reservoir. Get that special bleeder kit here. If you don't have that tool, you have to use a scan tool that has bidirectional capabilities and ABS software (minimum $500 scan tool).

How can you avoid getting air into the ABS system? NEVER, and I mean NEVER let the reservoir run dry as you bleed the brakes. ALWAYS, and I mean ALWAYS use a vacuum bleeder. The days of
pumping with the brake pedal are OVER. Don't believe me? Try it yourself. You may skate by.

But if you get air into the system and have to take it to a shop, be prepared to fork over at least $100 for a scan tool bleed procedure. (By the way, you could have bought the vacuum tool for a tad less than that).

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Block heater theory on GM vehicles

GM has installed temperature sensing circuitry into the plug on factory installed block heaters. It prevents the heater from operating unless it is colder than 0°F or -18C. It may seem insane, but it really does make sense if you understand why. If you install an aftermarket block heater without this circuitry, the PCM will see warm coolant, but a cold engine and cold air coming into it. Remember, it's the PCM's job to determine the correct air/fuel mixture. A cold engine block and cylinder head act as a fire extinguisher when you first start up the engine. So the computer commands a very rich mixture. How does it know what temperture the engine is? It used to look at only the coolant temperature. But now it looks at both coolant temp and the temp of the metal itself. If it see a discrepency between the two numbers, and the outside air temp coming in through the intake is 0° or above, it assumes there's something wrong with the coolant temp sensor and sets a trouble code.

Bottom line, if you add an aftermarket heater, it must have the temperature sensing circuitry in it or you WILL set a trouble code. Also, if you ever have to replace the power cord to the factory block heater, you must use a new GM power cable.

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Cruise control will not engage or kicks out

All cruise control systems have certain things in common. First, they must receive power from the ignition switch. Next, they must see a "brake off" signal from the brake switch mounted under the dash above the brake pedal. The most common failure point is either of these two parts. If the cruise engages and lets go, that's most often a sign of a brake switch that's intermittent, misadjusted, or has a short in the wires (head right for a broken wire in the connector if you own a Ford). In fact, even if you replace the switch, check the wires in the connector if you still get intermittent operation. If that checks out, test for constant power from the ignition switch to the cruise module.

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Take #2 on those oil filter "studies"

If you’re a motorhead you’ve probably seen the online oil filter studies where a self-proclaimed “non-lubrication expert” cuts apart oil filters to compare their construction. In my opinion, that “study” is short on actual testing and filled with assumptions and projections that have little to do with oil filtration. The study has an obvious bias against FRAM oil filters. It shows through the entire study.So, let’s take a look at the study “findings.”

Inlet holes

First, the study makes a point of discussing the small oil inlet holes on FRAM filters. But if you’re a car buff, you know that oil pumps are designed to build lots of pressure, but they actually pump very little VOLUME. That’s because oil pumps are a gear displacement design. They work by compressing oil in the very small void between two gear teeth. Simply put, you can’t pump a lot of oil in that small gap. And engines don’t need a lot of oil volume. If they did, 4-5 quarts wouldn’t be enough to keep the pan level high enough as the oil is being pumped up to the head and drizzling back down. So the whole point about small inlet holes, in the real world, is basically bogus. You don’t need large inlet holes.

The Square Inch Theory Doesn’t Measure Up

Next the study compares the number of filter media pleats and square inch count of the media itself. Now a rational person would read this and automatically assume that more filter media
means better filtration. But that depends on the filter media's efficiency. If a filter media with a larger surface but poor efficiency, it will larger particles through. In that case, what good is all that surface area? I’ve looked through the “studies” and keep coming up empty on the results for any filter media efficiency testing. I wonder why the study didn’t actually TEST the filter media to measure its filtration efficiency. Without that data, the study seems to be standing solely on a “more square inches is better theory” Until we know the efficiency of the filter media, the number of pleats and total surface area is irrelevant.

Of course, even if we did have efficiency ratings, the next question is, “How much surface area is enough?” Ah hah! There’s no good answer to that. Because even if we assume that you
change your oil and filter religiously every 3,000 miles, it’s the condition of YOUR ENGINE, what kind of AIR filter YOU use and how often YOU change it (which is based on actual conditions—not mileage), what type of driving YOU do, the operation of the PCV valve* (see footnote 1), and YOUR overall engine performance (worn spark plugs and wires produce more misfires) that determines just how much junk ends up in the oil and the filter. If you really take care of your car, drive “right” and install a filter with the lowest square inches of filter media, you may actually have more than enough filtering protection. That would make the
study’s assumptions irrelevant—which is my point. More on how much is enough later in the story.

End Plate Thickness

Really, I almost laughed out loud on this one. The end plate is what threads onto your engine. It pulls the rubber gasket up to the mating surface. As the gasket meets the mating surface,
it compresses. As long as the end plate keeps the gasket compressed, it has done its job. Extra thickness beyond what is necessary to hold the gasket against the mating surface is
simply useless. I’ve seen plenty of oil filters leak at the gasket area—but the leaks are ALWAYS caused by over torqueing the filter and splitting the gasket, or installing the new filter over on top of a stuck gasket from the previous filter. Bottom line, the whole end plate discussion is bogus. The question is really, how much thickness is enough. And the answer is: It has to be thick enough to compress the gasket—period. Anything thicker is a
waste. My take on the end plate thickness discussion is that it’s useless information that doesn’t contribute to the quality discussion at all.

End Cap Construction is a You-Get-What-You-Pay-For Issue

Now we’re talking turkey. Let’s say we have a filter material that’s very efficient and the pleats are well formed. But if the oil rides up or down towards the end caps and those end caps aren’t sealed properly, it’s all for nothing. The oil will take the path of least
resistance and seep past the end caps and down the center tube. It won’t open the bypass valve. It will go between the pleats and the end cap. Here’s the bottom line, regardless of which filter manufacturer you look at, they all make cheap filters for the economy-minded consumer. And cheap filters have cheap end caps. It’s that simple. One of the “better” manufacturers in this “study” makes a private label filter for a large retailer. Cut that
puppy open and you’ll find fiber end caps glued to the pleats. Do they work? Yup. Will they last 7,000 miles? Doubtful. But they’ll probably do just fine for 3,000 miles. So it doesn’t make any sense to compare the construction of a $9 filter to a $3 filter. If you fill your crankcase with expensive synthetic oil and slap on a cheap filter, well, don’t be surprised that the filter won’t go the distance—regardless of which brand you choose.

Anti-drainback valve construction is also related to filter price.

Nitrile is cheap. Silicone is more. Guess which material a manufacturer will use for the anti-drainback valve on a cheap filter? Do you need silicone? Maybe. If your filter is mounted
sideways or at an angle on the engine, the oil in the filter will drain back into the engine at shutdown unless it’s stopped by the anti-drainback valve. An empty filter means a delay in building pressure at startup—the most critical time for an engine. So the anti-drainback valve can be very important, depending on where your filter is mounted and how long you keep it in service. If your filter mounts end-plate-up, the whole anti-drain back valve issue is a moot point—oil doesn’t drain straight up. Nitrile anti-drainback valves DO harden up and lose their sealing ability as they age. So if you don’t change your oil on time AND your filter is mounted at an angle or sideways, quit being a cheapskate and buy a filter with a silicone anti-drainback valve. All cheap filters have nitrile valves. Silicone valves are either orange or grey. Just look through the oil inlet holes and check the color. Enough said?

The Story of the Lonely Bypass Valve

The bypass valve is like the Maytag repair man--it's idle most of the time. Its job is to bypass oil past the filter media if the media is plugged.* (See footnote 2) What does it do the rest of the time? Nothing. When does the filter get plugged? When the oil is loaded with crud. Why is the oil loaded with crud? Because YOU don’t change your oil on time and you don’t take care of your car. If you don’t care enough to maintain your car, why do you care if the oil is bypassing the filter?

Seriously folks, this one is a no-brainer. I read the studies and I can’t find where anybody actually TESTED the bypass valves to see if they leaked. Instead the study seems to rely on a letter from a guy who says he worked for FRAM years ago. That guy says the bypass valves were molded from plastic and they weren’t formed well. The guy didn’t sign his letter because he’s afraid of being sued. Do we know if his information is real? Nope.

FRAM manufacturing plants meet ISO 14001 and ISO/QS 9000 quality certifications. Don’t know what ISO quality standards are or who ISO is? Read this:

“ISO (International Organization for Standardization) is the world's largest developer and publisher of International Standards.

ISO is a network of the national standards institutes of 161 countries, one member per country, with a Central Secretariat in Geneva, Switzerland, that coordinates the system.

ISO is a non-governmental organization that forms a bridge between the public and private sectors. On the one hand, many of its member institutes are part of the governmental structure
of their countries, or are mandated by their government. On the other hand, other members have their roots uniquely in the private sector, having been set up by national partnerships of
industry associations.

Therefore, ISO enables a consensus to be reached on solutions that meet both the requirements of business and the broader needs of society.”

For more information on ISO, go to www.iso.org

So here we have a study that was conducted by a “non-lubrication expert” who cuts filters apart in his basement but doesn’t actually perform any tests, and a letter from an obviously disgruntled former FRAM employee. On the other hand, we have an international standards organization that certifies quality at every major manufacturer. Who are we to believe? If you don’t think ISO certification is important, then perhaps you discount the fact that Champion Labs is also certified by ISO. Is their certification bogus too? Don’t get me wrong. Champion Labs makes great products and they also make really inexpensive filters under private label for large retailers. We owe them and FRAM the benefit of the doubt that they’ve tested their filters in real world conditions and the filters passed the tests in order to gain ISO
certification. To me, that’s a more important indicator of quality than a study that’s biased against FRAM—a study that apparently didn’t actually perform any tests. (Feel free to correct me if I’m wrong about that point)

Is there a High Mileage Hoax?

The filter study really bashes the High Mileage filter by FRAM. Is a high mileage additive a gimmick? All the major oil manufacturers seem to offer high mileage oil. Are they in on the same scam? I said I’d get back to this when we discussed how much filter media is enough. Now is the time.

Oil is clean when you pour it in. But then it gets dirty. How? Well, first, no matter how new your engine is, combustion gasses ALWAYS seep past the piston rings. That’s right, piston rings aren’t a continuous circle. There’s always a gap. So the high pressure of compression forces combustion gasses through all 3 piston ring gaps and into the crankcase. That gas is called “blow-by.” The makeup of blow-by gasses varies depending on the condition of the engine and the efficiency of the burn. If you have worn spark plugs, you’ll have more misfires. That will put more UNBURNED gasoline and soot into your crankcase. The gasoline will wash sediment off the internal engine parts. The soot grinds away at metal parts, like bathroom cleanser. The oil carries the sediment, soot, and crud to your oil filter (But that’s only if you haven’t depleted all the dispersant additives in your oil. If you have, then all that crud will settle to the bottom of your oil pan where it will form SLUDGE). If your plugs are in good shape and the engine is running at high efficiency but you do lots of short trips, you’ll
end up with a lot of condensation in your crankcase. What are many engine components made from? Yeah, steel. Water + steel = rust. Water + combustion gasses= acid. Oil contains anti-corrosive additives to fight rust and neutralizers to combat acid. But if you run your oil past it’s expected life OR make short trips, OR your engine has a lot of miles, YOU WILL DEPLETE THOSE ADDITIVES AT A FASTER RATE. High mileage oil has more of these additives. Don’t use high mileage oil? Maybe you could add those additives back into your oil by installing a high mileage oil filter. Ah, so FRAM isn’t so crazy after all.

Now let’s take a look at the study’s complaint about the FRAM High Mileage filter and the plastic gel holder. The complaint is that the gel capsule obstructs oil flow. When the filter is new, hot oil flows through the pleats and down the center tube. But if the gel capsule is blocking the return of the oil, the oil filter should pressurize and blow up, right? Or, it should pressurize and blow the gel into the oil pump, right? But that doesn't happen. Why?
Because the study’s assumptions are WRONG.

As the hot oil flows down the center tube, it DOES hit the top of the gel. But then it rolls down the BACKSIDE of the pleats. It exits the oil filter through the holes in the bottom of the capsule—the holes that aren’t blocked by the gel. Over time, as the gel dissolves, it opens more holes. Once it’s completely gone, the oil goes straight down the center tube. If you’re following me, you see that the whole point of this design is to force the hot oil to
hit the gel and then flow around it as it dissolves it. If the flow rate for oil was 20 gallons per minute, maybe he’d have a point about the obstruction. But remember, engine oil is high pressure, low flow rate. So, if you own a high mileage vehicle and want to replenish acid neutralizers, anti-wear additives, and dispersants, the gel capsule is a great way to do it. Plus, buying a high mileage oil filter is actually cheaper than buying 5 quarts of high
mileage oil. Don’t like the gel idea? Fine. Don't buy it. But don't follow the study’s biased assumptions and bogus theories about oil obstruction when they aren’t true.

There is a bottom line to this.

Every filter manufacturer makes high and low end filters. Want a high end filter? Great! Spend more and buy one that’s made with synthetic glass/cellulose filter media, mesh pleat backing,
a metal core tube, metal end caps, silicone anti-drainback valves, and spring operated bypass valves. Oh, and buy a filter from a manufacturer that’s ISO rated for quality.

As for an oil filter “study” that doesn’t actually test the efficiency of the filter--well, take that for what it's worth. It's an opinion piece, sprinkled with a few irrelevent facts.

My disclaimer

I do NOT work for FRAM. I do not make any money off of FRAM. They're a large filter manufacturer owned by an even larger and extremely well respected manufacturer (Honeywell). Honeywell makes lots of electronics components for the automotive industry. They also own Prestone. They own Bendix brakes. They’re a major player in the automotive industry. They are one of the largest manufacturers of heating and air conditioning controls in the world. In short, they're no slouch outfit. I wrote this opinion piece because I didn't think the oil filter study was nearly as objective the authors would have us believe. And, I saw lots of people quoting from it as if it were the "bible."

Always remember this: Never believe anything you read on the Internet--not even my stuff. This is all my opinion. Don't take it as anything more than that. Now take a deep breath and read
the footnotes


1. In the old days, car makers let blow-by gasses run out a tube on the back of the engine. Blow-by gasses create smog. They contain soot. In other words, they pollute. What to do with
blow-by gasses if you can’t eliminate them? Yeah, burn them. So car makers suck the blow-by gasses out of the crankcase and into the intake manifold. Wouldn’t that create a vacuum inside
the engine? Yes, except that car makers allow fresh FILTERED air in to replace the gasses that were sucked out. See where I’m going? If you don’t change your air filter or you have a leak
in the air duct, you suck DIRTY air into the crankcase. If you drive in dusty conditions, you can bet you’re going to suck in more dust. Where’s the PCV in all of this? Well, the job ofthe Positive Crankcase Ventilation valve is to close off the route from the intake to the crankcase in the event of a backfire. But since the PCV is always sucking blow-by gasses and some oil vapor, it can clog up and restrict the flow. When that happens, more crud stays in the crankcase. How do you test a PCV? Shake it. If you hear a sharp metallic sound, it’s good. If it feels mushy, chances are it’s gunked up and should be replaced. Unsure? Replace it. They’re cheap.

2 There are times when the bypass valve can open even if the filter isn’t clogged. Multi-viscosity oil is supposed to flow well at low temps. But flowing well at -20° is a relative term. There are instances where cold oil can build oil pressure inside the filter
casing to the point here it forces the bypass valve open. However, once the oil heats up, the bypass valve should close because the bypass spring pressure will be greater than the resistance offered by the filter media. The real question is this: if the oil is cold and
thick at startup, is it carrying contaminants that should be filtered? Maybe so, if the there’s crud on the bottom of the oil pan. But if you’ve ignored oil changes to the point where you’ve got that sludge buildup, why do you care if the bypass valve is open. Your engine will be toast soon anyways.

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Rick's new website

Rick's new website makes it easier to find what you're looking for.

It's still a work in process and transferring over 200 articles is taking longer than I thought, but the new website is up and running. If you don't find what you're looking for here, try this site:

RicksFreeAutoRepairAdvice.com

Pass this link on to friends!

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High mileage oil and oil filters—worth the money?

Look around the oil section and you’ll find several companies now offering oil and oil filters specifically designed for high mileage vehicles. You never needed high mileage oil or special filters before, so what makes you think you need it now? Plus, what’s in that oil and those filters that makes them suitable for high mileage vehicles?

Plenty!

All engines (even new ones) have blow-by. That’s the combustion gas that squeezes past the piston rings and into the crankcase. But high mileage engines have more cylinder and ring wear and thus more blow-by gasses. That’s why oil in high mileage engines turns black much faster than the same oil in a new engine. As your engine wear, you’re literally blowing trash into the crankcase. It’s the oil’s job to take out the trash and the additives help it do its job.

Oil is made up of 25% additives. Those additives contain anti-corrosion chemicals, anti-foaming agents, anti-wear compounds (mostly zinc), and acid neutralizers. High mileage oil has a higher percentage of anti-corrosion, anti-wear, and acid neutralizers than traditional oil. Older engines need that extra protection because they wear out the additives faster. In addition to those additives, high mileage oils also contain seal conditioners. Nitrile seals get brittle and crack as they age and heat takes its toll. Seal conditioners soften the Nitrile seals and make them more pliable. That means fewer leaks from seals.

If you don’t feel like spending the extra money on each quart of high mileage oil, consider this special filter from Fram. Their HM (high mileage) filter contains a cartridge filled with additive gel. The gel sits inside the core tube of the filter and slowly melts as hot oil flows over it. The end result is additive replenishment.

©, Rick Muscoplat

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Oil Viscosity Warning

When car makers specify a certain oil viscosity range based on outside temperatures, they MEAN it. Today’s vehicles use hydraulic oil pressure to operate timing belt and timing chain tensioners, and more variable valve timing devices. Using the wrong viscosity oil can disrupt the variable valve timing operation and throw cam timing off. That will set a check engine
light and trouble code. Improper cam timing can result in poor performance and rough idle. Car makers have made it known that they will NOT pay for warranty claims based on improper oil viscosity. Worse yet, if tensioning devices do not work properly, it can result in jumped teeth and major repair costs. Finally, improper oil viscosity on a cold start can result in hydraulic lifters that literally “pump up” and bend push rods. So follow the car makers viscosity recommendations and quit trying to second guess their
specifications.

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Testing a fuel pump

Fuel pumps in fuel injected vehicles is mounted inside the gas tank. It’s a major job to replace it and these pumps are expensive. So before you replace one, you better do your homework. I’ve seen too many DIY mechanics make the assumption that their engine running problems are due to a bad pump. Several hundred dollars later, they still have the same problem.

If your diagnostics lead you to believe you have a fuel pump problem, here’s the proper way to check out the pump. First, perform a fuel pressure test. You’ll need a fuel pressure gauge and the adapters to fit your vehicle. Some auto parts stores rent this test gear. You’ll also need the specs for your vehicle. Check out a printed or online shop manual for those.

Perform the fuel pressure check first thing in the morning, with the engine cool. A cool engine provides two things: better working conditions with less chance of a fuel-spill related fire, and a more accurate reading of residual fuel pressure after sitting for a long time. Fuel pumps have a check valve that prevent the fuel from draining back into the tank when the engine is shut off. If the valve isn’t working properly, you’ll have fuel drainback and that causes hard starting first thing in the morning. Shop manuals have a specific procedure for performing this “leakdown” test if the vehicle is brought in warm with high fuel pressure. Usually, the tech looks for pressure to stay within 5 lbs of the running pressure.

If your fuel pressure and leakdown readings are within spec, you’ll need to check fuel delivery volume. Yup, that’s an important test especially if your performance problems occur at high speeds or heavy throttle. Some manufacturers list a volume of fuel for a specified period of time. If you can’t find a spec, use this rule of thumb—a fuel pump should deliver 1 quart of fuel in 30 seconds. If yours passes that test, move on to the electrical tests.

The electrical test can spot a fuel pump problem that evades all other diagnostics. Remember, the pump is always pumping against resistance (the pressure regulator and he fuel injectors). Just like any other electric motor that meets resistance, it uses more power. So like an EKG at your doctor’s office, measuring current draw at different throttle openings tells you how the pump is performing. A properly operating fuel pump should draw from 3 to 6.5 amps.

If you own a scope, you can get even better readings. A scope will tell you if you have a bad winding in the pump since it detects every lobe on the armature.

©, Rick Muscoplat

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GM Anti-Theft Systems

GM has used a variety of anti-theft systems on their vehicles. When you get a no start, intermittent start, or start then die, you should diagnose the anti-theft system before you start replacing starting components. A tell-tale sign that you’ve got an anti-theft problem is a flashing “Theft” light. Here’s a brief primer on each system and what to look for.

Each GM anti-theft system disables different components. Some disable the engine starter, while others enable the starter but disable fuel injectors. None of them disable spark. So, first understand the difference between vehicle theft deterrent systems.

VAT
The VAT, or vehicle anti-theft was used primarily on 1986-88 Corvettes. The key had a pellet that was married to the vehicle anti-theft module at the factory. If the lock cylinder was turned or bypassed with the proper key installed, the system would disable the starter and kill the injectors. You could NOT perform a system “relearn.”

PassKey I, and II
Similar to the VATS system, these vehicles also used a pellet key. You can identify this system by looking at the key. It has a black resistor pellet with a thin metal edge running along the key. The system enables the starter, but shuts down the injectors after initial startup. So the vehicle would start, then die. This system has a “relearn” feature. It was used on these vehicles

Buick
Century 97-01
Park Avenue 91-96
LeSabre 92-99
Riviera/Reatta 90-01
Regal 94-99
Roadmaster 94-96

Cadillac
Eldorado 89-01
Seville 89-97
Fleetwood 92-96
Deville 90-99
Allante 89-93

Chevrolet
Camero 89-01
Corvette 89-01
Caprice/Impala 94-96
Lumina/Monte Carlo 95-97

Oldsmobile
Cutlass Supreme 94-97
Aurora 95-00
Regency/88 91-99
Toronado 90-93
Pontiac
Firebird 89-01
Grand Prix 94-96
Bonneville 92-99

PassKey III
This system uses a special key (PK3 stamped on the shoulder of the key) with a transponder under the rubber cover. The receiver module is located next to the lock cylinder. When the key is positioned next to the lock cylinder receiver module, it energizes the transponder which sends a coded signal to the receiver. The receiver module checks its memory to see if the
signal is correct. If it is, the module sends a signal to the PCM to enable the engine. You cannot test this system with an ohmmeter. You need a scan tool. If the signal is not correct, the PCM disables the injector and the starter. The system is used on:

Buick
Lesabre 2000-on
Park Avenue 97-on

Cadillac
Seville 98-on
Deville 2000-on

Oldsmobile
Aurora 01-on

Pontiac
Bonneville 2000-on

GM Minivans
Venture, Montana, Silhouette

Passlock
This system allows starter operation, then kills the injectors 1-2 seconds after startup. This is a “Hall-Effect” system. The key cylinder housing has a small magnet that rotates past the Passlock sensor. The sensor is powered and detects the rotation. The voltage on the sensor then drops to a specified value (there are 10 different values). There’s no pellet in the key. So basically this system is checking to see that a thief has not popped the lock cylinder to steal the vehicle. you have to perform a Powertrain Control Module (PCM) relearn procedure (need a programming scan tool). The Passlock system was used on:

Buick
Skylark 96-98

Chevrolet
Cavalier 95-on
Impala 2000-on
Malibu 97-on
Monte Carlo 2000-on

Oldsmobile
Achieva 96-on
Cutlass 97-on
Intrigue 98-on

All GM trucks 98-0n


SYSTEM DIAGNOSTICS

PassKey I and II System Diagnostics

There are 15 different key codes. Measure the resistance of the key pellet by connecting an ohmmeter to each side of the key pellet. Once you find the resistance value, remove the lower dash panels and locate two small wires (both white) that run down the base of the steering column. Disconnect the electrical connector where those wires terminate. Then connect an ohmmeter to that electrical connector and insert the key. The reading you get at the end of the two white wires should match the resistance value you got from the key. Next, turn the key. The value on your meter should NOT change or drop out. If it does, you will have to replace the key cylinder. It is COMMON for the wires to break from the key cylinder.

Passlock
Testing this system is similar to the Passkey I and II systems. You want to check the voltage at the bottom of the steering column as you insert the key and rotate it check the yellow signal wire (should be 5 volts before you start the testing). Turn the key.

The value should drop. If it does not, you will have to replace the key cylinder. The “control module” for this system is built into the instrument panel control (IPC) in early years. In later years, the system is controlled by the Body Control Module (BCM), the Electronically Controlled Orifice-steering Assist (EVO), IPC and other systems. If you have to replace the lock cylinder or any of the control modules,

Passkey III

You cannot check this system with an ohmmeter. You will need a scan tool to watch the operation of the system and find the trouble code. Once you get the trouble code, follow the diagnostic procedure based on the specific code.

©, 2009 Rick Muscoplat

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Oil filters -- Economy versus premium

In the old days I always believed that if you changed your oil on a regular basis (like every 3,000 miles) you could get away with any old bargain oil filter. I never had any hard evidence of the difference between the bargain filters and the name brand ones. Now I do. I did some research and then cut a few of them apart. I could see the differences right away. You will be
too.

A high quality oil filter is built from quality components. First, it must have a quality filter media. Most economy filters are made with cellulose that’s only about 80% efficient. But a multi-layered premium filter is made with cellulose and synthetic glass fibers that are 99% efficient. That extra filtration traps more harmful particles. Next, the filter must have enough surface area to keep filtering for the full life of your oil change. That means more pleats, and that costs more money.

But it’s not just an issue of more pleats. As oil pressure pushes against the pleats, they must have support from behind or they will squash. So manufacturers secure the tops and bottoms of the pleats and support the backside with a core tube. Economy filters, (like the one shown here) have a plastic core tube that only partially supports the filter media. The
premium filter has a metal core tube and metal pleat retainers. The FRAM filter shown here even has metal mesh supports behind every pleat. That extra support keeps the pleats from collapsing even after extended run periods and extra long oil change intervals.

Next, the filter must have a bypass valve. A bypass valve opens during periods of high pressure. It allows oil to bypass the filter media and drain down the core tube. Because if the filter media gets totally plugged, the oil pressure can destroy the tin can. Some car makers install a bypass valve in the oil pump, so those filters don’t need the valve. This particular economy filter skipped the traditional metal spring-loaded bypass valve and relies
instead on a combination anti-drainback/bypass valve. It rubber valve collapses during high pressure cycles. That allows the oil to drain down the center tube as well.

Finally, the filter must have some type of anti-drainback valve to prevent dry startups on vehicles where the filter is mounted on its side or at an angle. Economy filters use a Nitrile valve that can harden and crack after 3,000 miles. Premium filters use a silicone anti-drainback valve that can last the entire length of an extended oil change (7-10,000 miles). It’s easy to tell the difference between the two materials—nitrile is black. Silicone
is either orange or light gray. You won’t find silicone valves on economy filters—they just can’t afford to use those costlier materials.

All this is fine if you do your own oil changes. You can pull a filter out of the box and check for a silicone anti-drainback valve and be reasonably sure that you’re not putting a crummy filter on your engine. But what if you’re at a quickie lube place? Those places buy their filters in bulk and from what I’ve seen so far, they’re not the $8 dollar filters. In fact, an automotive wholesaler near me offers oil filters for $1.49—and I don’t have to buy in
bulk. Imagine what my price would be if I bought them by the truckload.
I checked with a lube place and asked for their price on a regular oil change and one with synthetic oil. Then I asked which filters they used for both changes. You guessed it—the same filter. The tab on the synthetic oil change was $62.95 plus a disposal fee. So if you’re planning of having a shop do the actual oil change, you may want to buy a premium filter and
bring it with you. It’s better to pay a few bucks extra, than to have them install one of those cheapo filters that’s not even rated for 6,000 miles. As a final note, the FRAM filter shown here is rated for extended oil change intervals.

©, 2009 Rick Muscoplat

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Busting the Copper Spark Plug MYTH

It’s common knowledge that copper plugs are the best choice for all engines. Right? Well, there are a few caveats, so the legend goes. First, everyone knows they don’t last as long as platinum or iridium. But the improved performance you get from copper plugs is supposed to make up for the more frequent changes. If only that myth were true.

It isn’t!

Vehicles with distributorless ignition systems (DIS) fire the spark plug from the center electrode on the firing cylinder. But to complete the electrical path back to the ignition coil, the return electricity must jump from the SIDE electrode back to the center electrode on the firing cylinder’s “partner.” According to Autolite engineering team, “although copper spark plugs may function well initially, they are not designed to handle the needs of a DIS engine and will likely fail prematurely.”

The engineers add, “Copper core single platinum spark plugs are not designed to withstand this reverse polarity firing and will suffer premature gap growth due to center electrode erosion. Gap growth will stress ignition system components by requiring more voltage to fire,” said Dave Buckshaw, Honeywell CPG trainer for the FRAM® and Autolite® brands. “This degradation can be noticeable as soon as 20,000 miles after the plug is installed.”

Buckshaw adds that many consumers don’t realize that very few new vehicles still use copper core spark plugs and those that do – like the Chrysler® 5.7 Hemi V8 – specify a 30,000-mile spark plug change interval.

Double Platinum plugs are specifically designed for engines with DIS systems and are 30 percent more durable than the average of leading competitors. The platinum-to-platinum firing offers virtually no gap erosion and performance that lasts for up to 100,000 miles. Autolite’s proprietary platinum alloy and welding process on the Double Platinum plugs provide superior engine performance, longer life, improved fuel economy and easier starts.

Autolite XP Xtreme Performance® spark plugs designed with an iridium-enhanced .6mm finewire are also compatible with DIS engines. These ultra-premium plugs require less voltage to fire and have a faster flame kernel growth in the combustion chamber resulting in a better, faster, more efficient burn compared to the .8mm finewire, multi-electrode design and standard plugs. Not only does this increase fuel economy, but, according to Autolite engineers, igniting more gas and air mixture inside the cylinders will result in improved throttle response and acceleration.

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Chevy Silverado Lock Cylinder Problems

Owners report problems with the lock cylinder on their 2003-04 Chevy Silverado trucks. The problem is either a binding lock cylinder, ignition switch, or the park lock cable. The best way to isolate the problem is to remove the shroud from the steering column and then remove the lock cylinder and the park lock cable. Then stick a screwdriver into the lock cylinder bore to engage it with the linkage to the ignition switch. Turn the screwdriver to see if the movement is smooth. If it is, that eliminates the ignition switch.

Next, reinstall the park lock cable and repeat the test. If it now binds, replace the park lock cable. If both of those components check out, the problem is in the lock cylinder. Before replacing, try applying anti-seize compound inside the bore. If that doesn’t work, you’ll have to replace the cylinder.

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