Hi there, I recently bought an 89 Si 4ws which wasn't running. Turns out all it needed was new spark plug wires, so that's fixed now. But it's still having some other issues.

For one, the idle sometimes bounces around between 1.5k and 2.5k. This happens after the car warms up. Reading up online, all signs seemed to point to needing a new fast idle valve, so I got one, replaced it (which was a bitch to do), but the problem remains. Any ideas of what else it could be?

But the real problem is that the engine sputters at high RPM or at full throttle. If I slowly glide up to high rpms, it starts sputtering at about 4.5k. If I put full throttle, it'll happen at a much lower rpm. When it happens, the electrical system seems to cut out momentarily too, and I hear relays triggering in the dash. I've tried on 2 distributors, adjusted the timing, and resistance tested the ignition coil, and everything there seems to check out okay. My next guess may be a bad ground. I wasn't able to check all the ground points today because it got dark, but I'll do that next time I work on the car. Would this be a symptom of a bad ground? Any other ideas of what this could be? Maybe it's a problem with the fuel? If it wasn't getting fuel though, would that cause the electrical to momentarily cut out as well?

Thanks for the help.

 

Sign up at prelude power dot com(no space) you will get all the resources you need on that forum than on HT.

PP.com has the biggest following with the most support or information on symptoms and write-ups with pictures this side of the Pa-coast.

 

Cool, thanks for the tip. There's definitely a lot of great info there!