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How is Dodge Spark Advance Controlled by the PCM if there is a Distributor?

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 ...
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4 votes
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How are new cars (with HO2Ss) affected by cold starts?

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 ...
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3 votes
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Why do modern PCMs prefer MAP over MAF

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 ...
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3 votes

PCM Bench Testing

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 ...
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3 votes

Replace or Repair Mazda MPV 2000 faulty ECU?

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 ...
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2 votes
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Replace or Repair Mazda MPV 2000 faulty ECU?

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 ...
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2 votes
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Vehicle does not start after installing new ECM

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 ...
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2 votes

2006 Mazda 5 2.3L cranks but no start

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 ...
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  • 131
2 votes

Programming error Buick Enclave 2008

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 ...
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2 votes

ODIS 5.0.6 diagnostic tool : how can I remove an option from a transformed vehicle?

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 ...
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2 votes

MAF sensor output signal vs. RPM?

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 ...
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2 votes

After odometer/mileage correction, which module data gets changed - engine or instrument cluster?

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/...
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1 vote

How to open Ford PCM

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 ...
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  • 3,175
1 vote

Why wont my truck start?

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....
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  • 21
1 vote

Is Jeep and Dodge's, both 6.1l SRT8, PCMs interchangeable

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 ...
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1 vote

Is Jeep and Dodge's, both 6.1l SRT8, PCMs interchangeable

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 ...
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1 vote
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2003 Chevy Cavalier: Why does acceleration sometimes stop working properly?

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, ...
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1 vote

Backtracing: P0606 (PCM fault) to P0716 (Input Speed Sensor) to Faulty Gearbox

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 ...
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1 vote
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Live scan tool for OBD 1.5 GM transitional?

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 ...
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1 vote

Live scan tool for OBD 1.5 GM transitional?

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 [...
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  • 11
1 vote

1999 Grand Prix Issues

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 ...
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  • 15.9k
1 vote

1999 Grand Prix Issues

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. ...
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  • 11

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