PCM problems
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Joined: Jan 2011
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PCM problems I Just bought a 95 T/A from a guy said it needs a new PCM i got it home and put a reman PCM in it and still has the same problem IE will crank but not turn over i have checked the spark put on a new opti and made sure it was geting fuel i have also got a obd1 reader and can not get it to connect to the PCM any ideas wold help thanks
I will never understand when people say "it will crank but won't turn over." The two are one in the same. Say something like "it will turn over (i.e. the motor spins) but it won't fire (or start)". The terminology is nutty.
Almost 100% of the time the PCM is NEVER at fault. Most PCM failures happen from people who lose connection to the PCM during programming of an aftermarket tune.
Any mods or is it stock?
You say it's getting fuel...what kind of pressure are you getting at the fuel rail?
How did you check for spark? Do you have spark out of the coil? Out of the opti?
Also, check the optispark harness connections for continuity. Any broken wires in the opti harness can cause an intermittent problem.
The OBDI code reader you have, is it designed to work with the OBDII-type connector that the 95s are synonymous with? Chances are, no - not many are 95-compatible.
Provide more info. Then, provide MORE. The more you provide the better your chances are of getting a good logical answer.
Almost 100% of the time the PCM is NEVER at fault. Most PCM failures happen from people who lose connection to the PCM during programming of an aftermarket tune.
Any mods or is it stock?
You say it's getting fuel...what kind of pressure are you getting at the fuel rail?
How did you check for spark? Do you have spark out of the coil? Out of the opti?
Also, check the optispark harness connections for continuity. Any broken wires in the opti harness can cause an intermittent problem.
The OBDI code reader you have, is it designed to work with the OBDII-type connector that the 95s are synonymous with? Chances are, no - not many are 95-compatible.
Provide more info. Then, provide MORE. The more you provide the better your chances are of getting a good logical answer.
[QUOTE=RamAir95TA;14393486]I will never understand when people say "it will crank but won't turn over." The two are one in the same. Say something like "it will turn over (i.e. the motor spins) but it won't fire (or start)". The terminology is nutty.
[QUOTE]
OMG.... I can't see!!! I think I'm having a heart attack...
[QUOTE]
OMG.... I can't see!!! I think I'm having a heart attack...
TECH Regular
Joined: May 2010
Posts: 481
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Almost 100% of the time the PCM is NEVER at fault. Most PCM failures happen from people who lose connection to the PCM during programming of an aftermarket tune.
Any mods or is it stock?
You say it's getting fuel...what kind of pressure are you getting at the fuel rail?
How did you check for spark? Do you have spark out of the coil? Out of the opti?
Also, check the optispark harness connections for continuity. Any broken wires in the opti harness can cause an intermittent problem.
The OBDI code reader you have, is it designed to work with the OBDII-type connector that the 95s are synonymous with? Chances are, no - not many are 95-compatible.
Provide more info. Then, provide MORE. The more you provide the better your chances are of getting a good logical answer.
Any mods or is it stock?
You say it's getting fuel...what kind of pressure are you getting at the fuel rail?
How did you check for spark? Do you have spark out of the coil? Out of the opti?
Also, check the optispark harness connections for continuity. Any broken wires in the opti harness can cause an intermittent problem.
The OBDI code reader you have, is it designed to work with the OBDII-type connector that the 95s are synonymous with? Chances are, no - not many are 95-compatible.
Provide more info. Then, provide MORE. The more you provide the better your chances are of getting a good logical answer.
Are you handy with a multimeter? It sounds like your not getting spark from somwhere. Now that I'm thinking of it where did you get the pcm from? Some places don't put a tune on the pcm, they leave that up to you.
Steps on how to diagnose ignition problems under tech aids:
http://shbox.com/page/index.html
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Verdad Gallardo Test everything and question everything. It's a must do when you buy someone elses problems. Start simple and check fuel pressure first, check to make sure plugs and wires are good and that the wires are routed correctly. Then start testing ignition stuff. Is the opti giving off singnal, is the coil getting signal, is the coil firing? do I have spark at the plugs? then contiue through to fuel. Is it getting fuel? is it getting air? if you have all of that time to look internally. There is not much to make an engine at least try to fire. fuel air spark is it. check out shbox.com for how to info.
Teching In
Joined: Nov 2010
Posts: 11
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97 z/28 to 94z/28 Engine Swap I wrecked my 97z still driveable.I decided to put the engine in a 94z.The 94 was missing the pcm,bcm, and the rearend.I also have a 95z for which I took the pcm,and the bcm.My question is will the modules work from the 95 or the 97.The car turns over but will not start.This engine was running right up until I took it out.My problem I think lies in the modules I think.
^ WTF?
1) Don't hijack threads
2) Your post makes no sense
3) You talk about a 94 and a 95, then suddenly a 97.
You're an idiot.
OP: Jaycenk is right. Need more info, and you need to start with basic diagnostic procedures to find out more. Most problems have a huge multitude of possible causes, and the more you check, the more you eliminate off the list.
1) Don't hijack threads
2) Your post makes no sense
3) You talk about a 94 and a 95, then suddenly a 97.
You're an idiot.
OP: Jaycenk is right. Need more info, and you need to start with basic diagnostic procedures to find out more. Most problems have a huge multitude of possible causes, and the more you check, the more you eliminate off the list.
Only if all was just in the world....
anyways, check EVERYTHING. All of the fuses, look for broken wires, listen for fuel pumps to kick on....EVERYTHING.
Like someone said, You might not have a tune loaded to the PCM.
I once had a bad voltage draw while i was loading a tune on to the pcm and it fried the memory chips, had to get them replaced. many different things could be your problem. Just find out all the info you can on what IS WORKING then we can help from there.
anyways, check EVERYTHING. All of the fuses, look for broken wires, listen for fuel pumps to kick on....EVERYTHING.
Like someone said, You might not have a tune loaded to the PCM.
I once had a bad voltage draw while i was loading a tune on to the pcm and it fried the memory chips, had to get them replaced. many different things could be your problem. Just find out all the info you can on what IS WORKING then we can help from there.
