dbrockma

I did a search and found lots of info, but nothing that jumped out at me as 'my issue'.

Bought a 95 z28 M6 convertible, drove it for about 2 weeks now with a high voltage 'tick tick' ocassionally. Seemed to drive fine but sometimes at high rpm it would ocassionally cut out and run rough. Had it to the SMOG place and it was kind of dark and the guy said look here. There was a 1/2" spark gapping between the boot of the coil wire on the coil to the base of the coil plug. I figured it was a cracked coil, so I hopped down to OKragen and picked up a new coil, IGM and plug wires.
Well, I carefully grinded the old coil off the brackets, cleaned em up and put everything back together, got it installed and started it up and it idled.... much much better than it did. Not having one of these cars for several years I guess I forgot. Gave it some gas and it revved IMMEDIATELY, much better than the 2 weeks I had it.
So, off I go and it seems like it has twice the power it did, up to 3k RPM, then always cuts out and sputters. I double checked all the wires, connectors and grounds for the stuff I put on and the MAF and intake air sensor cause those were jiggled when I put the coil pack in.

I suppose I could have purchased a bad unit, and the IGM did not have the silicone thermal paste in the box like it was supposed to (I had some from another car) but I really don't want to trouble shoot a problem like this again.

I checked the air filter, fuel pressure (at idle it was 49 PSI, but the gauge would not reach out the hood when it was closed, but it ran fine most of the time before. The car has 146k on it and had recently (about 5-7k miles ago) had the water pump, opti, heads, cam, fuel injectors, plugs, wires all new (and I have receipts from the shop that put them in for the previous owner)

Any areas to check first? My first thought is to put the old stuff back (before it is squished in the trash compactor) in, and see if it gets better, then change one item at a time but I figure with the experience we have on here someone may point out something I am missing, or a better starting point than 'start over and do one piece at a time'

Oh, the check engine light is not on even though it was running like crap and I don't believe the 95's have the smarts the newer cars do for the scanner to catch, but I'm going to do that now.

dbrockma

Well, my OBDII scanner had a 'read error', first time I have seen that. I put it on my 2001 Suburban and it read it fine. This car is a 95, and my 96 it read fine too. Is 95 possibly ODB I? Do I need to purchase another scanner?

Injuneer

Yes, the 95 is OBD-I with a 16-pin OBD-II style connector. You need an OBD-I scanner, with a 12-pin to 16-pin adapter, or you need to use jumper wires, as shown by Shoebox:

http://shbox.com/1/xraycable.jpg

You can also use free scanning software like Freescan or Datamaster, with the correct cable:

TTS Power Systems

FreeScan

This source used to sell cables, but I believe he now has a link to a new source:

AKM Electronics Home Page

dbrockma

Thought I would give an update...

After messing with my OBDII scanner, using shbox.com (which I donated, one BIG resource for us!) and thinking about my other car (in my sig) that is STILL in pieces.... I took it to a local shop.

They found a bad wire going to the MAF that was grounding out, so indeed when I replaced the coil/icm I had moved the wires. While it is there I'm having them look into why it idles rough. I know some of it is because it has an aftermarket cam, but as the guy doing the work pointed out, at a steady state above a certian RPM it should run evenly.

Since this is more or less a street cam I think I agree. Unless there is something I am missing?

I suppose once it is running right I will poke it on a dyno for a baseline for future mods.

Injuneer

Who tuned it for the cam? What is the present mods lisf, since your Signature appears to refer to future mods or some other vehicle.

Grant.J.Galant

Hey guyz i own a 1996 3.4 and i love her to bits...... Few days ago the needles on the clocks started jumping while driving......then yesterday i get in ....insert the key turn it but get no acc or ignition lights......if i turn the key all the way she starts over just fine and i get lights on dash but i have to hold the key there..... Once i let go it all shuts down again.......

I checked all the fuses ect........any advice.......shes automatic.....

Injuneer

Tacking a new problem onto an old thread, pretty much unrelated to your problem is not a good way to get results. Best thing is to start a new thread, in the correct forum.

Also need to understand what you mean by "the clocks started jumping".... are you referring to the instrument panel? .... the tack and speedo, specifically? If so, this can be a problem with a ground wire, but need more detail on exactly what is happening and what it is happening to.

The problem with the key is most likely the ignition switch, and the flickering instruments may be related. See if this info helps with regard to describing your problems, and suggesting the source:

4th Gen F-body Ignition Switch Replacement

Might also want to clear up - there is no 1996 3.4L.... the 3.4L was discontinued in 1995. You should have a 3.8L.