94 Z28 loss of power/surging

[Paul94Z28]

Hi-

I have 94 Z28 with 78K miles on it. I started to experience issues this summer with the car not having power. It started when I would it up and it had a big miss. Then it ran like junk the whole way home. I recently installed an MSD so immediately suspected that. I bypassed it and it is still present (even worse actually). I have Datamaster and have taken captures with and without the msd attached. The car is back off a few degrees of timing for sure. I would be happy to share the captures if anyone could help with the analysis. The plugs are new that are in factory looms and wires under long tube headers. The car previously ran fine. I have had this car since 96 and am pretty familiar with it. I am on the original coil, icm, and opti though.

Any help would be appreciated.

Thanks,

Paul

[wrightz28]

Wondering if the coil is/was a bit to worn for the MSD? Just my only thought at the moment.

[Paul94Z28]

The problem I am running into is it is slightly BETTER with the MSD, as if the MSD is making the issue. I am gonna try a known good coil/icm and test and see what I get (provided I can find one)

[Paul94Z28]

Ended up being plug and wire issues. I replaced and added some asbestos insulator boots.

We should be good.

[wrightz28]

Heh, thought you said they were new? Off-brand?

[Paul94Z28]

Everything was new, AC Delco wires and NGK plugs. Plug wires seem to get funny when heated. I added the asbestos boots and it seems to be fine now.

[wrightz28]

Gotcha.