96 WS6

I'd like to first say that if I can't figure this problem out I'm going to end up selling the car and building a turbo mustang. I'm so sick of this crap...

I won't bore you with the history and I will just skip to the symptoms. The car misses if you give it too much load off the line. While driving, if I nail it, it will run good (smooth, no hesitatation) and sometimes I can feel it hesitate. At the same time, the A/F ratio seems to get richer and richer as the RPM's increase. I think it may due to a weak spark or something. Also I have a problem where my wideband meter (the only digital gauge I have) cuts out and resets while I am flooring it. Driving around normally, it never cuts off.

My voltage is perfect. Battery is an optima yellow top, fairly new. Ignition is delteq with wires I cut myself and brand new autolite 104 plugs painstakingly gapped at .032".

I could go on and on about what the car does but I doubt it will help... I have almost no hope left. I have tried everything. I have tunercat, a wideband a/f meter, all kinds of scanning equipment, multimeters everything. I cleaned a resanded every ground I could find. I just need some advice on how to proceed I'm completely lost on this car... every single car that I have a ever built for other people works perfectly. When it comes to my own car... it runs like ****. I'm sick of it...

1racerdude

Have ya taken it to somebody to have it diagnosed?

96 WS6

No, and frankly I don't plan to. You have to understand. I spent 2 years working at an Fbody shop. I know the car like the back of my hand. I'm not going to take it to a shop that knows as much or possibly less than me, especially about electrical issues.

There was a time for about a month when the car ran perfectly. Then I let my former boss sit in the driver's seat to show me to do a burnout on slicks. He was a stupid idiot and overrevved the car, bouncing off the rev limited doing a rolling burnout for about 30 seconds while also destroying my friend's ET streets. That was the second time I let somebody other than my brother drive my car... I should have learned my lesson the first time. Anyway, after that, the car never ran the same. I have replaced the entire ignition system, checked the pushrods for alignment, readjusted my rockers, and replaced my valve springs with comp 918 beehives. The compression is a perfect 210 across the board. If that story gives you a clue as to what happened... but I doubt it will.

I think I'll just convert to a carb setup. Much easier to deal with.

OBE1 95Z28

Have you looked at your knock counts?

1racerdude

It looks like ya are lost on this on though.

After the burnout I would look for broken valve springs,week springs,bent valves,bent push rod's and the like. Flat lobe on cam too and a broken roller lifter.
Did ya do a leakdown test? A compression test won't tell the truth all the time.

Injuneer

I've seen posts on other boards (e.g. - fbody.com) where the misfire was traced to the Delteq. In those cases, Delteq admitted that the unit just won't work on some cars, took the unit back and refunded the cost. Have you considered the possibility there's a problem with the Delteq?

96 WS6

OBE1 - After I put my wot timing down to about 26 or 27 degrees I had no knock across the board.

1racerdude - That is the first thing I checked. In fact, a few months down the road I had a valvespring break on me (luckily I killed it before it took a valve with it). They were those crappy CM612 springs, the EX component ones. Now I have comp 918 beehives with all the lightweight goodies along with my hardened pushrods, comp 1.6 promags (non-sa), and old style comp R lifters (never had issues with them).

Injuneer - I did not know they had compatability issues with the delteq... I will have to investigate this further. I am pretty cool with JC because at my old shop we were going to become dealers but it never went through. He has offered to send me a new delteq box to see if that's the problem. I might try that, but I always have my good old Jason Cromer opti to fall back on. Thanks for the heads up.

I had an interesting revelation today... about 2 hours ago infact. I have a gold plates battery terminal with one 0 gauge, one 2 gauge, and 2 4 gauge terminals. I use one of those 4 gauge terminals to run from the battery to the alternator (the zero gauge goes to the fuse block in the hatch). I felt it by chance today and it was moveable by light touch... not exactly loose, but moveable. I slammed the thing down really quickly (over the top post) and took it for a ride and it's no longer hesitating!!! I think it may have just been a loose battery terminal. You guys are probably thinking wow this guy must be a moron to be in desperation over a loose battery terminal but I assure you, there must have been some other problems that I most likely fixed, but they were masked by the loose terminal because I know for a fact it wasn't always loose. I will post back and see if this is really it...

Oh and I think this confirms my theory of weak spark causing the hesitation... thanks for jogging my brain!!

Injuneer

My experience with with JC goes back to his days at Electromotive and the infamous "Opti-Eliminator/SDI". Mine would just cut off at random times (hmmm.... wonder if I had a loose battery terminal ), felt like the engine hit the stock rev limiter. He seemed to suddenly become "unreachable" when I tried to trace down the problems. I see too many parallels between problems with the O-E/SDI and the Delteq.

96 WS6

That's hilarious... it's funny how people sometimes become unreachable. The best part is when you finally do see them and they are stunned... At that point you really don't want to see them at all, what you really want is to see the expression on their face or the loss of words in their voice.

I have a feeling that the delteq is working fine... I won't work on the car until friday but I'll let you know then how it went. In the meantime I am going to look for a battery terminal that fits better around the top post than the one I have. I am also going to add a new battery ground.

user 647483

Sounds like ignition to me, coil packs or wires.
Assuming the wires are working well (no arcing) and your plugs are firing correctly;
It'd almost be worth buying an extra coil pack and rotating it in to see if any of the existing ones are bad.

I can certainly understand your frustration. I went through similar issues with my 95 and the MSD DIS ignition unit and coil packs I was running.
Eventually, we just tore the whole thing apart and reinstalled it with new packs, adapters, plugs and wires. She ran awesome after that.

96 WS6

Hopefully the problem is already solved but i'll let you know. It's really easy to test a coil pack too...

Did you notice a significant performace difference with the MSD box installed? Or was it just used mainly for the added functionality?