I took my 1996 honda civic dx hatch back to the shop and they told me i needed a new pcm because my check engine light was on. Can this cause your check engine light to come on? I have searched the web to try and find one but i cant find one anywhere. If you know some websites or places that sells pcm's that would be awesome. i got to pass inspection.

 

a bad pcm can make your check engine light come on.. i believe the code is p1607 wich is (PCM) Internal Circuit Malfunction.

and check ebay or craigslist for another one.

 

he's telling you that you need to replace your ecu basically. in vehicles post 1995 the ecu is referred to as the pcm. 1995 and prior are referred to as an ecm. Just because your check engine light is on doesn't mean you need a new ecu. it means you need to pull your codes and figure out what the problem is. The only reason you'd need to replace it is if the one in there now is completely fried. in the event that you do need one you'll be looking for a P2E ecu.

 

ok sweet. yeah man i replaced both oxygen sensors already, my cat is fine, i kept reseting the ecu but the cel still wouldn't go off. They said i needed a new pcm. So i got to replace the whole ecu? The pcm and the ecu are not separate?

 

pcm/ecm/ecu. it's all the same thing. its just the one computer behind your passenger side footwell carpet. did you pull the codes? you can't just replace things at random hoping the code goes away lol. did they say they were unable to retrieve codes?

 

No man they checked the codes at shop. They said my oxygen sensor was running to low on ohms cause i had the wrong one. i replaced that reset the ecu nothing happend. i took it back they said the oxygen sensor was fine now but i might have fried my pcm from using the wrong o2 sensor. They said they checked the pcm out and said it was fried. It sounds like bull **** to me frying the pcm because of an oxygen sensor?

 

ecm/pcm/ecu... etc. They're all different names for the same thing: the computer that runs your car.

There are several hundred things that can cause a check engine light, and only a few are pcm related. I would ask your mechanic exactly what error codes it's throwing. He should give you one or more 4 digit numbers, starting with P... like "P1607." Actually, P1607 *IS* one of the codes for a major pcm malfunction.

If he won't give them to you, you can borrow a scantool for free from Autozone, O'Riley's, or most other auto parts stores. You plug it into the port under the dashboard on the driver's side by the door and follow the instructions they *hopefully* give you. It should tell you what error codes it's throwing.

If you can post the error codes here, we can probably tell you if your mechanic is BS'ing you or not... and maybe give you some pointers on what the actual problem is.

 

any follow-up info? i'm in the middle of the exact same problem.