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5

While the vehicles are equipped with a distributor the innards of that distributor have changed quite a bit. The distributor no longer contains flyweights or any mechanical timing controls, instead it contains the camshaft position sensor. The way the system works is, readings are taken from the crankshaft position sensor by the PCM. The PCM then ...


4

It's true that heated O2 sensors shorten the time the engine is in open loop. So the whole "wasting gas thing" while you wait for the engine to warm up isn't as big an issue. But there are many other reasons to not sit and warm up your engine. The most important one is that warming your engine will warm the coolant, but it doesn't warm the oil as quickly as ...


3

In the turbo applications I am familiar with, both a wire or film (better) type MAF is used, in conjunction with a MAP, IAT, ECT, etc. Specifically on turbosupercharged Subarus, there's knowledge to be gained by also knowing intake pressure. Ultimately, you are trying to reach the best AFR. Things change a bit when supercharging, whether mechanical or ...


3

It's very hard to tease out what your actual problem is. Here is what I've figured out. Your truck won't start and you have no communication with the PCM. This makes you think that the PCM is bad. How am i doing? First, a PCM can't be diagnosed outside the vehicle without a big complex setup that simulates all of the vehicle it should be hooked up to. ...


3

I'd advise against repairing ECU's, and splurging on a brand-spanking new one is, in my opinion, excessive. Get one from the junkyard, make sure the vehicle you are pulling it from has the exact same options, exact same engine, exact same transmission.


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It is much more likely that the IMRC is damaged. The voltage on the line between pin 1 and pin 42 is provided by the IMRC. The PCM then pulls that voltage to ground to turn the IMRC on. When the IMRC is on the voltage on pin 5 drops to below 1v. In your case the the voltage between pin 1 and pin 42 is always below 1v. This could mean one of two things. ...


2

There are steps to replacing an ECU. Find detailed instructions here. Basically: Disconnect the battery and let the car sit for 15 minutes. Plug the new ECU in, reconnect the battery and turn the key to "accessory" or "on", whatever turns all your warning lights on. Your Check Engine Light needs to be on at this stage or your ECU is defective. Let the car ...


2

It turned out it was an intermittently open wire to the cam position sensor. Unfortunately between then and now one of the mechanics bent the valves by installing the intake cam upside down so I still don't have a working car.


2

P0602 simply means the control module is not programmed. Programming is generally required when installing a new PCM in most modern vehicles. You will need to take the vehicle and the new PCM to a shop with the specialize equipment to program the computer. There really isn't a DIY solution to this problem.


2

This may or may not apply to the Bentley In general, stock ECU's are not programmable from an options standpoint. Writing to the ECU is not allowed, they are read only. Aftermarket ECU's take output from sensors and frequently stand in serial to the stock ECU so the aftermarket can modify information and act as a proxy to the sensor, essentially emulating ...


2

I think you misunderstand the purpose of the Mass Air Flow (MAF) sensor (and whoever wrote what you read doesn't understand, as well). The purpose of the MAF is to read the amount of incoming air. As the incoming air flows over the heated sensor, it cools the sensor which regulates the amount of electricity which can flow through it. It is in no way ...


2

Millage correction is possible on ALL vehicles and it does have its legal uses. Peugeot/Citroen suffer from a bug where the BSI gets corrupt and the millage changes to a random value, Landrover 2005/07 to around 2014 also had a issue where if a instrument cluster was incorrectly programmed it would put 99999 miles on the clock. Then there is obviously the ...


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Rubber mallet and pry tools. Hammer the first one in at back corner and then just slowly pry them open going all the way around it. I have special pry tools I made but you can get it done with flat heads screwdrivers. I used to use heat but its only helps a little so not worth the extra effort and care needed for the hot case. The only detail you really need ...


1

I've had an experience where I took my vehicle in to an car audio/electrician place to get a remote starter checked and possibly removed. The next day my car did not start and was not accepting my key. It went into the anti theft mode too. I called the place back and explained it to them and they fixed the issue free of charge. If Dodge did a flash I would ...


1

They're not going to be compatible. Look at the code on the PCM, and then look it up on an interchange site; you'll find that Jeep and Dodge 6.1 engines never come up in the same list. Also, to make the PCM work in another car - even one where the PCM is a direct replacement - it needs to be programmed to the cars VIN and Mileage, and the keys need to be ...


1

There are a couple of things which I believe would make it so I wouldn't do that: More than likely, even though they are the same base engine (6.1L Hemi), they are still tuned differently. The variance in the tunes could introduce unforeseen problems. If it is a bad PCM, how do you know if whatever caused it to happen might not do that to the swapped in PCM?...


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I would start by testing the full sweep of the Throttle Position Sensor (TPS). These can go bad in a way that creates intermittant problems. The wiper area of this "potentiometer" can wear, especially around the idle position, and create all sorts of havoc with driveability. This can occur without throwing a OBD diagnostic code, because the PCM has no way ...


1

On some cars, the input speed sensor to the transmission and the output speed sensor work in tandom. The computer can tell which gear the transmission is actually in and even adjust the harshness of the shift. If one sensor has actually failed, typically the car should go into a limp home mode. Are you sure these are current error codes or simply stored ...


1

I have an Actron CP9145 that reads obd 1.5 on my 1995 GMC Jimmy. does not read ABS or Airbag though. Bought it new for $135 a couple of years ago. Don't remember if I got it on Ebay or Amazon. I know this is an old thread but I hope this helps someone.


1

I have a 95 Chev Astro 4.3 Vortec V6 with the transitionary OBD1.5 connector and I use a Craftsman Scantool CanOBD2&1 Kit, part number 920899 (about $300+ US back around the turn of the century [2000]), to read the codes and reset faults. It works. It has always worked. I bought it to talk to my '86 and '88 OBDI TransAM WS6 GTAs which it does quite well. ...


1

An ECU is an engine control unit. A PCM is a power train control module. They are the same thing. Automakers love alphabet soup. I would start my investigation at the coolant temperature sensor. A CTS normally reads -40 when it's unplugged or there is something wrong with the connector or wiring like an open or corroded/deformed pin. A simple way to check ...


1

Yes. Had a friend who changed motors. New motor had a slightly different cam otherwise exact same motor. He spent $4000.00 changing parts to get the car to run right. He finally gave up and sold it. He found out later that because of the cam change he needed a different model ECU. Good thing he works in a parts store. If you have a different engine that's a ...


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