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EFI Ignition problem. Please HELP!!!

I started the car today with a fully charged battery and she ran dine. As stated earlier the volts must have been low enough to cause injector problems.

Tonight I will unplug the steering column harness and see what happens. I have determined that both the horn and flashers are on the courtesy light circuit.
 
The flashers may well be on the courtesy light circuit, but the horn signal comes from the headlamp switch. Now then, given that you have a GM wiring harness, all bets are off with what should be on that light circuit.

Isn't GM a PO?
 
"Midlife" said:
The flashers may well be on the courtesy light circuit, but the horn signal comes from the headlamp switch. Now then, given that you have a GM wiring harness, all bets are off with what should be on that light circuit.

Isn't GM a PO?
Click to expand...

Ahhhhh....I forgot that little detail.....
 
I firged out the problem. When I put the bulb back in the courtesy light it came loose a little bit from the housing that holds it to the dash. I was just enough to cause the short. Everything works well now. Well everything but the flashers but that is another topic. I guess that mean I can't break down on the side of the road. :thu What a wild goose chase this electrical gremlins can be. Now I know why it confuses me..... :confu

Thanks for all the help guys!!!! Now maybe I can go get a sound clip of the car. One with the mufflers and one with the cutouts. :thu
 
Well I still have the problem. Now more confused than ever. Last time I start the car and she purrs like a kitten. This time same as the time before. Engine light on, running what appears to be very lean, smoking out the back, misfiring. Voltage on the battery was 11.7 when I tried to start it. I charged the battery up to 13.5 and it did the same thing.

I then pulled the engine codes and got 5.
15 -basically the battery was disconnected
84,85 are emission related and I don't have that on my car
81 - Intake air control circuit fault/ air injection diverter/air diverter solenoid (I think this means a problem with IAC and it needs to be replaced but parts store could not confirm)
82- there are a couple descriptions that come up for this one. #1 is air diverter solenoid circuit fault or supercharger bypass circuit fault. #2 Integrated relay control module.

I think my problems are in 81 and/or 82. The both could mean I need to replace the IAC but I would like to get your perspective before I throw parts at this thing.
 
This is probably way off base, but I'll throw in my 2 cents. When I had some weird troubles and strange codes (one was the IAC), I ended up having a grounding issue. I had taken the computer out, and forgotten to hook up the ground wire coming out of the case when I reinstalled it. I hooked up that wire and viola, all was back to normal. It's hard to see in the photo, but it's a bare wire that, IIRC, grounds the case. So, make sure all your grounds are good.
 

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Good idea and I did not remember any ground that close to the computer. I pulled the glove box door off and found that there isn't a ground on my harness there. I am using an RJM harness and wonder if the ground that is connect to my engine is the same on that Ford puts under the dash. Are you using a Ford harness or is it aftermarket?

Tried starting the car again and it sounds scary. I turned it off. Sounds like marbles in the engine or something. I assume that noise is deotonation. I don't think anything is seriously wrong mechanically. It ran great a couple days ago (idling in the garage and a couple throttles to 3k rpm). I am starting to think something has to be wrong with the ignition system. Something that is not constant but irregular.
 
Well the wonder of the web just taught me that codes 81, 82, 84 & 85 are for lack of emissions. I really am confused as to wtf to do.
 
That close ground may be incoporated in RMJ's harness. I took the harness out of an '89 GT and modified it to work.

I'm assuming that you've removed all of the smog equipement from the car -- I know that I did. All of those codes should be gone because of the tune. There only a couple of scalars in the programming to get rid of the smog codes. I wonder if you're chip has fried...and you're back running the stock ford tune. With any major modifications to the engine, the stock ford tune will run like crap. Even a simple cam change can make the car run like crap without getting it tuned.
 
Interesting idea. I think it is about time for me to call the tuner. Last thing I want to do is blow up the engine.
 
Not good news to report. I have a mechanical problem and likely an electronics problem. My engine guy came over and we started to chase down the noise. We thought it was a friction sound and stared to remove accessory belts, blower belt and it was still there. We drained the oil and that looked good. We then stared to pull the upper intake so we could get to the valve covers. Everything there looked good. Removed the dizzy to see the oil pump gear and make sure it wasn't a pump problem. That checked out fine.

We then pulled the radiator so that we could turn the engine over and that is where it started to get interesting. The exhaust valve on cylinder 4 makes a weird noise when it is compressed. Not sure what is going on so I will have to pull the lower intake. He feels that it may be one of two things. Either the dog bone broke and is causing the lifter to twist or the lifter went bad. Brand new Comp Cam performance lifters.

When I was building the engine the builder said that I should step up and get tie-bar lifters and avoid the dog bones since he has seen them fail in HP applications. I did not hear of anything like that so I stayed with them and saved a couple hundred bucks.

The only good thing I can see coming out of this is that I have had a oil leak that I haven't been able to stop. If I pull the engine I should be able to take care of that.

I sure hope that my electronic issue is related to this but I would be surprised if it is. I am pretty bumbed right now.
 
That sucks, hopefully it won't be that bad once you tear into it. God speed man, hope you get it figured out easily and cheaply :)
 
I took off the lower intake and did not like what I saw. I have a broken dog bone on cal #7. I hope I caught it early enough it did not cause major damage. I will take the engine out to repair and have everything inspected. I finally have a chance to fix that oil leak I guess.

The biggest concern I have is that it took out my custom grind cam. Time for some tie bar lifters and maybe a bowl blend on the heads. If it costs me money to fix it I might as well make it faster.

Any recommendations for great litters? Evidently really nice Comp Cams lifters are not good enough.
 
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