Resolved 2G Help with no start diagnosis

[Henny101]

Okay so i am having a bit of trouble diagnosing my no start. I had it running a few days ago but when I was working on it i made a noob mistake of not disconnecting the battery and well one of my alternator wires came off and arced on the O2 sensor. Since then it has not wanted to start. So far i have tested,

-Compression which is 180 across all cylinders

-fuel pressure which was 42 psi

-It does have spark

-I know the timing is right

-I tested the ECT, it have a reading of 1884 ohms which is a little low i think but i doubt that could be causing the problem

-I tested the CPS and CAS, Both were showing readings when cranking

-Injectors are firing, i listened to them tick and i tested the harness with a voltmeter

Any suggestions on what i should test next to help me figure out what is wrong would be awesome.

The car is a 95 eagle talon with a 97 motor in it, the spark plug wires already have been swapped. I still need to swap the injector trigger wires but i know thats not what is causing it not to start.

Thanks
Henri

 

[Pauly D]

does it crank ?

nevermind it obviously does since you got spark but look at your fusses really closely during the arc one might off blew out

 

[FugitivE]

Check the simple things like fuses? Might have fried the ecu. Do you have a spare to test?

 

[accidentaldsmer]

Alternator switch probably blew it's the big 100 amp one which is held down with two bolts.

 

[FugitivE]

Just thinking, maybe you damaged to o2. Do you have link? If so try locking the car in open loop mode to see if maybe it's the o2.


Its not the Alt fuses, the car would still start with no Alt unless battery was dead but then it wouldn't crank either.

 

[AZN29]

You made sure no check engine light,right? I wanna say that if it arced,it blew a fuse....check both boxes.

 

[SmoochDarling]

Try a different power transistor. I reverse polarity'd my electrical system and it would not fire, switched it and it fired right up. This power transistor is often the first thing to blow if you short out your battery etc.

 

[Henny101]

I checked all the fuses under the hood and none of them were blown. The car still cranks over no problem at all, but it does back fire when i try to start it up. Also im pretty sure the ECU is still good because from what i have read if the check engine light comes on then goes off it is still good. As well as if the stock boost gauge moves then it is a sign the ECU is still functioning.

I may have ruined the O2 sensor but even if i did it should still start up as im pretty sure the car doesnt use the O2 sensor on start up. It operates in closed loop until the O2 sensor warms up too 600F.

I have not tried a different power transistor. Is there a troubleshoot i can do on the power transistor to see if thats the problem.

Thanks
Henri

Turns out it was just the spark plugs were fouled i changed them and it start right up