Right next to the red + terminal block.

Some data logs could be helpful in your search for the problem.

 

The passenger side fender...there is a red plastic block that is the + node for the electrical system and then the - cable bolts to the fender just to the left of that.

 

What kinds of things do you think I should be looking for? I do know that each cylinder will register missfire counts.

I was watching fuel trims yesterday on my way in from work and it would run very rich at 70mph steady cruise (-6%/-10%) then with moderate throttle it would go lean. I've had a split at idle forever and have not been able to fix it, it may be that random misses are skewing the 02 readings making the PCM adjust incorrectly.

 

I couldn't imagine how frustrated you are right now. I would also say that since you have the dash lights flickering, it is electrical.
Maybe somehow it isn't providing enough constant electricity to your injectors or something. Could it be fuel starved? Have you checked your injectors?

My mechanic has a machine that he plugs into the opti and can watch each cylinder. He can see the spark, everything. That was the easiest way for me to make sure everything was even on both sides. What I am saying is, when a car almost cuts off, stutters, ect. It could also be fuel related. Just giving you ideas here.

Get some log data. I have the CC306 w/ heads, ect. and at idle
my Scanmaster shows 128/159 It is perfect on the left, but the right is showing max rich on the Scanmaster. But when I start driving, it smoothes out, 127/128 ish.

When I am at speeds of like 50-70 cruising, I get a little tiny miss as well. But when I put it in D, it seems to stop it. Just weird.

One more thing, look under the hood in the dark, and look for those infamous sparks

Keep us updated, I want to know what it was when you find it.

 

Injectors are new SVO 30#'s and the fuel pressure is good. I'm almost certain at this point is has to be electrical and not specifically ignition related.

I only see about 13.3v while running rather than 14.4. I rebuilt the alternator last spring and it did nothing.

 

You mention 13.3v. My 95 and other f-bods are right there at that. Sometimes I will see it from 12.9-13.0 I have never seen a 14.4v on the Scanmaster, or just w/ a battery checker.

I have an Optima red top, less than 2 years old. These voltages have stayed the same before and after a new alternator. Funny,
I also have SVO #30's and having some of your same problems at cruising speeds. I am tempted to take them out and try my old set.

Keep us posted. Run data logs.

 

i don't think it is injector related b/c when he has the SVO 24 #s in from the old setup it was still having this problem, isn't that right Chris?? so stepping up to the 30s didn't cause the problem to start or go away...

 

Correct.

Also there's no underhood arcing going on either. Even before the LTCC I checked for that and there was none. Now, the wires are only like 8" long and come nowhere near each other, so its definitely not the issue now.

 

I never said it was an injector problem, just suggested he check them out. B/c stuttering can be fuel related. And at this point, it wouldn't hurt to check.

And I mentioned the 30#'s b/c I though it was ironic we had the same kind, a little of the same problem....

 

I have the EXACT same problem. I have worked on this thing for 3 months! I have done everything that you have done and then some. Coil, plugs, wires, opti, pcm, msd, afpr, new ground straps, checked wire harness. It even spent 3 days in a speed shop and they couldn't figure out what was causing it. It feels like you are fighting a soft rev limiter, doesn't it? Sometimes worse, sometimes not so bad. I have no vacum leaks and no ignition problems and the injectors are firing perfectly. I changed to a monster cam and decked the heads and now all hell has broken loose. And no, it's not detonation, either. I suspect lifter collapse may be occuring. I have over 400lbs of open spring pressure with an extremely steep lobe. I'll let you know it that fixes it on sat, that's when my comp r's get here. It did the same thing on the dyno, busting up pretty bad. It still made 432lbs rwtq and over 400rwhp with her rocking back and fourth. If I ever get it fixed, I guess it was worth it. I'll let you know if the lifters help me this weekend. Good luck,
James

 

Well I actually do have some news to report.

I snooped around under the hood some more this afternoon.

There is a wiring loom/harness running behind the alternator. The red wire from the weatherpack connector goes in there, and there is a green and a black wire coming up from somewhere on the bottom and I believe run up over the top of the motor and back to the PCM.

Well, both the green and black wires are quite crispy from coming into contact with the #2 header primary.

I'm going to strip and splice them tommorrow and see if it helps. Wondering what those wires go to and suspect the black one at least could be a ground for the ignition?????

EDIT: Well those wires just go to the a/c compressor....I'll repair them but doesn't look like that's the problem.

 

Chris whats up. Listen I am having a similar problem and I was told that it is the fuel pump, but I am with you on the thought of it being electrical and infact maybe a ground issue. I would like to know if when you open you key as if to start the car and do you hear as if their is a false contact somewhere. That is what I am hearing and also my air pump starts spooling and the lets go and the starts spooling again as if their were a bad electrical conection. I have been working on this myself and it is driving me bananas. I hope one of us find out what the f(%$ is wrong. PLease reply letting me know if you have the same or similar symptoms.

P.S Does your engine turn as if it wants to start but doesn't? That is what I am also experiencing.

Thanks and luck to the both of us.

 

Today I stripped and re-insulated the crusty A/C wires, checked all my grounds including the ground strap, and I scanned at idle some.

nothing unusual to report except 13.5v ignition and the fact that it registered "NO" Hi Res opti signal. Low res was like 20.1 at 850 rpm, but hi res literally said "NO". Is this unusual?

I also pulled some plug wires and injector harnesses while running. Every one made the car run worse except for #6 and #8....there was not much difference between having the injector clip on and off on either of those two. Was able to pull the #6 plug wire too and that didn't seem to make much difference either (#8 is too hard to get to while running). I can tell you #6 and all the other ones that I pulled wires from were getting plenty of spark, I have a small electrical burn on my wrist to prove it now.

How likely is it that the PCM is faulty, re: injector driver failure? Could be the harness but I wouldn't think I've ever done anything to cause damage to the harness, particularly around the injector plugs.

 

Just for grins, have you checked fuel pressure and the vacuum hose to the regulator for gas? When you said #6 and #8, that makes me think of when people have problems with the regulator leaking and pulling fuel into the vacuum line. It tends to dump fuel on 6 and 8, because of the location of the vacuum port in the intake manifold.

 

The hose and regulator are good...that's been checked.

OK, the mystery deepens. I just did the old shadtree trick of spraying water on the header tubes while the car is running.

Once the car idled for a minute or two to build some heat, the water quickly boiled off all primary tubes EXCEPT #2....it would just slowly evaporate off of it no matter how long I waited and re-applied.

I tend to put more stock in that than the injector plug test, not sure why but it seems more empirical to me.

I think I'll reset the pass. side valves tonight, maybe one of the #2 valves is just a tad too tight.