Finished!! Forged piston block, Custom valve head (flowbenched)

[NA2ndgen]

Last sunmmer I took my injector harness completely apart. I cleaned it, and I reinsulated it with liguid electrical tape. The main injector harness plug from the firewall was badly degraded by heat and grease too. I thoroughly cleaned it, and then I remade the plug body with black RTV. I also zip tied that plug, up and away from the rear valve cover, to prevent that mess from happening again.

[Ondonti]

Well since both engine harnesses work on the spirit I am giving that the benefit of the doubt.

[NA2ndgen]

Sounds reasonable, but be sure to clean the connectors and the main plug thoroughly, and recover any iffy looking insulation. Use dielectric grease on all the connectors and main plug too.

I bet you have that baby up and running real soon now.

[c2xejk]

Quote:

Originally Posted by Ondonti Well since both engine harnesses work on the spirit I am giving that the benefit of the doubt.

Which means that the problem is with something you are not swapping...

One thing that has struck me you said the front plugs were wet and the rear were carboned... You might consider new plugs. You can kill a plug with a splash of fuel... Talking with a spark calibrator, he has said that once this happens, the plug will not come back (atleast not with out pulling it and cleaning it.)

One theory floated out there is that the injectors are stuck on. A test for this would be to pull the injectors and rail. Put a container under each one and observe (CAREFULLY!)...

What other electrical issues have you faced?

[mwinkle353]

have you thought about getting a "noid" light?

put this on your injector plug and crank the motor. If the light flickers or is dim(timed with injector), then I'd say you're good. But if the light seems to stay on most of the time or is bright, then you quite possibly have a faulty ground to from those injectors to the PCM. They may be grounding due to a bare wire touching the chassis.


Another test would be to pull the fuel injectors and rail out of the intake. Then crank the motor. This might tell you wich injectors are firing and what are not. Plus you can witness the injectors spray pattern as well.



Just a thought,

Wink

[detobias]

Quote:

Originally Posted by mwinkle353 Another test would be to pull the fuel injectors and rail out of the intake. Then crank the motor. This might tell you wich injectors are firing and what are not. Plus you can witness the injectors spray pattern as well. Just a thought, Wink

I do this when swapping injectors to *make sure* the injectors & wiring I'm installing actually WORK! a lot easier than trying to diagnose a misfire or stutter after it's all together

only takes couple minutes; having a friend to turn over key while you witness injector operation helps.

put the cigarette out first

[Ondonti]

Im not using dielectric grease because that seems to be the kinda stuff that is gooped up in my connector. I want everything Dry.

As far as injectors being stuck open, I dont think thats the deal because the 2 that seems to be slightly grounded are on cylinders that are not flooding out.

I did pull the plugs last week, and open up the spark gap. They were set at .030" because that is what I ran when I had the turbo on (and it ran fine), and now I have them at .045" Didnt make a difference. Im gonna play with the harnesses now and compare the grounding #'s now that I have cleaned them and see if there are any differences between harnesses.

[NA2ndgen]

Quote:

Originally Posted by Ondonti Im not using dielectric grease because that seems to be the kinda stuff that is gooped up in my connector. I want everything Dry.

If you really want everything dry then use a small amount of dielectric. It fills in the gaps where water can condense on cool down, which leads to corrosion, and you do not want that.

Just use less. Trust me a little of that goo is a good thing.

[Ondonti]

Well after cleaning I didnt get any difference in the harnesses besides that now both of them pull about .19V.
I took one of them apart. I dont see any electrical problems.

[Ondonti]

I took the entire harness apart, then I put it on the engine and tested it again. Even when i can see the entire wire is not touching anything, I still get ground.

[Reaper1]

Man, you are running in to a similar issue I had with my van...I tired everything I knew, chenged everything I could...damn thing STILL wouldn't start!! I hope your luck is better than mine!!

[Ondonti]

Im gonna swap lower intakes and put one in that has stock injectors that I hope arent having problems.

[m90daytona]

Quote:

Originally Posted by Ondonti I took the entire harness apart, then I put it on the engine and tested it again. Even when i can see the entire wire is not touching anything, I still get ground.

well then the only place you can be getting ground from is the ecu...right? disconnect it at the ecu.

[c2xejk]

Quote:

Originally Posted by Ondonti I took the entire harness apart, then I put it on the engine and tested it again. Even when i can see the entire wire is not touching anything, I still get ground.

How are you testing this?

[Ondonti]

measuring voltage from the battery positive to the pins that used to be in the subharness plastic connector (i took it apart).

This means the only thing that is in the test is the injectors and the sub harness.

I can see all the wires in the harness and there are no shorts.


I read .2v on all the injector harness wires @ the connector.
If I remove the injector harness.

I read
0.0
0.0
0.03
0.07
0.1

On the 6 separate injectors when I directly measure them on their 2 pins. Each pin, pos and neg of the injector reads the same voltage (aka either 0.0 or 0.03, etc)