Progress Thread Error P0204 - Gray Smoke Out The Exhaust. (raw Gas Smell)


New Member
Nov 17, 2016
I need help and advice for error P0204. Any advice or ideas are welcome. The details are below.

The story
I started up my car and noticed that it was having trouble idling. Then I noticed the smell of gas. Then I noticed a huge cloud of gray smoke when I tried to accelerate. Then the check engine light came on. I pulled the codes and got Error P0204 - Injector Circuit Malfunction.

The Suspects
From what I understand, there is 3 possibilities

  1. The Fuel Injector
  2. The Engine Wire Harness
  3. Or the PCM

What's been ruled out

It's not the injector
I replaced the injector with a new one and tried swapping injectors around and still had the same problem. I also used an tried listening to the 4th injector. It's the only one that doesn't make a ticking sound. However, on injector 4, I think I do here clicking sometimes.

It *might* not be the Wire Harness
My dad did a test on Pin 100 of the PCM (model MDE2) and found that it wasn't shorting out. I'm not sure about this test though. The Pinout we used wasn't for the same model PCM. Mine is model MDE2. If someone could confirm that pin 100 is for Injector #4, that would help a lot.

It's also possible that when we did the test, it just wasn't shorting out at that moment. So I'm not very confident about this.
The next step
I bought a "new" MDE2 PCM of ebay. I should have that by Wednesday. I will test it out and post my results here.

If anyone has any advice or other things for me to try out, please post your ideas below. Thank you.
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