Electrical/Idle issues

[krislin]

So i've had an S13 for several years now, and never seem to work out my damn idle issues. It's a redtop, with most of the bolt-on's you can get, but nothing internal done, and still the original turbo, cams, etc. I've replaced the temp sending unit, plugs, ignitor, IACV, double and triple checked for boost leaks, a couple thermostats, boost controller, messed with the A/F ratio, new O2 sensor, etc etc etc. It finally idles good most of the time, but randomly starts to wonder about between 500-1000 rpm. I see a voltage drop from about 13.5V down to 12.5, then back to 13.5 just before the rpms drop (voltage down, revs down, voltage up, revs up). It'll do this for 2-5 minutes, then idle normal again. I've done the re-grounding of the the sensors as I found on this site, new cables for the alternator, battery is brand new. No power steering, no A/C. What else...S14 alternator...all electronics seem fine, but the lights do flicker with the voltage.

Ground issue, maybe? Not sure what would cause something so intermittent.

Thanks in advance.

[at23]

Timing perhaps?