What killed my computer?

Joey7508 · Feb 21, 2010

So here is what happened. Been running this a9p in my car for about 6 months. Today I drove it around came home parked it, and when I went to start it there was no spark. I went to pull codes and could not. I have pulled codes before so I know how. It wouldn't let me. I pulled a a9p computer out of my buddys car and put it in mine. Car started right up ran fine. I put mine back in my car and no spark again. So I am gonna get another computer, but I want to make sure it is not something I did to ruin the computer or something I should check before I put the new one in.

liljoe07 · Feb 21, 2010

What work have you done to the car to make you think it may be something you done?

Joey7508 · Feb 22, 2010

Nothing that I really did.However I did put a new ford crate motor in it 2 weeks ago, But it has been running fine no problems. But nothing differnent ecm or harness wise. I read a thread where you (liljoe07)had a guy check his 46 pin to ground. You said there would be vere very minimal voltage. Is that key on/off/cranking when should I see it and how much? Just trying to rule out any thing that I can check.

strtrcr50 · Feb 22, 2010

Was it a speed density swap? And regardless, open the case up and take a look for a burnt trace. Mine got one and had a lot of problems.

Joey7508 · Feb 22, 2010

I converted it for sd to maf about 2 yrs ago. I am looking for a burnt trace literally right now. I have it apart on the table don't see one yet.

Joey7508 · Feb 22, 2010

found one. The 46 pin trace on the back. Looking for more. Will that one keep it from running? What all will burn that one?

strtrcr50 · Feb 22, 2010

Joey7508 said:
found one. The 46 pin trace on the back. Looking for more. Will that one keep it from running? What all will burn that one?

Stop looking. You found it. And Yep.. It fugazis a lot. I fixed mine by soldering a wire across the trace. Odds are, you burned it by pulling codes trying to jump the hood light wire.

strtrcr50 · Feb 22, 2010

When mine burnt the trace from pin 46, it wouldn't idle, loaded up, and ran like hell..

Joey7508 · Feb 22, 2010

You think thats the only one? I am worried that maybe I did jump it wrong with the test light I had hooked to the battery, but I was only checking codes because the car would not start right after I drove it into my drive and turned it off. It would crank get gas, but acted like it was not getting fire/spark. No hint of a problem before that. So I went to [ull codes and couldn't get any. Thats when I knew something was up with the computer. So I took one out of my buddys car and it fired right up ran fine. I am borrowing yet another computer right now. Drove the car today, every thing seems good. Even pulled the codes just to make sure that end works. Got a 31 evp, fixed that currently getting 11 right now so all seems good. Just don't want to kill another one.

strtrcr50 · Feb 22, 2010

I'll bet that's the only one. Just take an 18 gauge wire and solder it across the two points and try it. I'm not quite sure why mine burned either. I was driving it and everything went to hell. I started doing pinouts and found that trace. Fixed it and everything was good. BTW, when you did the swap, what computer did you use and is your car a 5 spd or auto?

Joey7508 · Feb 22, 2010

Car is a 5 speed and the one that burned is a9p auto. I had an a9l before in the car. I swapped it out before to see if I could tell the difference between the a9l and a9p. While I had the a9l out another friend needed a computer so I sold it to him. The one in the car now is a9l.

strtrcr50 · Feb 22, 2010

Joey7508 said:
Car is a 5 speed and the one that burned is a9p auto. I had an a9l before in the car. I swapped it out before to see if I could tell the difference between the a9l and a9p. While I had the a9l out another friend needed a computer so I sold it to him. The one in the car now is a9l.

If you are putting an a9p ina 5spd, you have to move a wire in the o2 harness. If you have an a9l you should be good.

Joey7508 · Feb 22, 2010

the 02 harness I checked today and it is a 5 speed harness. I read that it doesn't matter which ecm you run in a 5 speed. But it does matter which one you run in an auto car? Not sure if thats right but it is what I read.

liljoe07 · Feb 22, 2010

Before you put the computer back in. Do a voltage check on PIN 46 at the ECM main connector. Need to do this check with the key on, and while cranking the engine over.

Joey7508 · Feb 23, 2010

what am I looking for as far as voltage? Should it be the same on and cranking?

liljoe07 · Feb 23, 2010

Should be very little,if any That circuit is a dedicated ground.

What happens in most cases, is that it gets blasted with 12v. Frys the computer. Either from hooking the code port to the Hood light, or the wrong 02 harness for the application. Or just some wiring Snafu.

Joey7508 · Feb 23, 2010

tried it yesterday but could not get a true reading. With key on it showed nothing basically,and while cranking it would go to 0.800 of a volt. My volt meter is a cheap pocket meter and seems to show .005 even when nothing is hooked to it? Thats what it was reading with key on? Should it read the same voltage key on and cranking? I appreciate all the help. Keep it coming.

liljoe07 · Feb 23, 2010

You should be good to go.

Solder the circuit and put it back in.

Joey7508 · Feb 23, 2010

Will do got the wire I needed today will let you know how it turns out. THanks again.

Joey7508 · Feb 23, 2010

solder it and it runs. Don't know what killed it, but I know what fixed it. Thanks liljoe07 and strtrcr50

What killed my computer?

Joey7508

Member

liljoe07

Joey7508

Member

strtrcr50

New Member

Joey7508

Member

Joey7508

Member

strtrcr50

New Member

strtrcr50

New Member

Joey7508

Member

strtrcr50

New Member

Joey7508

Member

strtrcr50

New Member

Joey7508

Member

liljoe07

Joey7508

Member

liljoe07

Joey7508

Member

liljoe07

Joey7508

Member

Joey7508

Member

Similar threads

What killed my computer?

Member

Member

New Member

Member

Member

New Member

New Member

Member

New Member

Member

New Member

Member

Member

Member

Member

Member

Similar threads

Privacy & Transparency

Privacy & Transparency