92 Stealth TT shaking,misfiring,stumbling when warm

[devianT]

Hello,

I've had this issue for a little while now, basically when the car is warm, it will randomly start misfiring, and it causes the car to shake pretty bad. It is intermittent, though, and sometimes you can go 10 minutes of normal driving around before it starts misfiring again. My ECU was rebuilt in like 2002 (as far as I know the caps were replaced).

My coil pack, plugs and plug wires are all recently new. PTU has also been swapped with a known good one, same problem. I also have my old (bad ish) ECU, when I put that in, I still have the exact same problem.

I am thinking other than the ECU, it's probably something related to the injectors and their wiring; about 7 months ago we had a bad injector, then a few months later, another different bad injector.

Any ideas what I should check?

[GTOJOE]

Have you done the fuel pump resistor bypass?

Stealth 316 - Fuel Pump Relay/Resistor Bypass

My car had a wierd stumbling issue and it turned out to be the fuel pump resistor. Problem went away when I did this.