I'm getting my '95 lt1 camaro ready for doing an emissions test.
I just installed new o2 sensors and there is no cat (we'll see if it can pass). I've reverted the tune -completely- back to stock except for the injector constant (I have 60lb mototrons). I've got the injectors dialed in to 62lbs and my long term fuel trims are right at zero while cruising, and it's holding an AFR of 14.7-15 according to my wideband.

The problem is at idle. It starts off at 14.7 AFR, then the RPMs starts loping and surging as the AFR bounces between 14.7 and a leaner and leaner reading (16, 17, 18). So the o2's are trying to correct it causing a bad surge, it's even died before.

I'm tuning with Tunercats and observing with Datamasters. My injectors are running at 1.1 - 1.3 mS at idle. Ive set the minimum pulse width to .9mS in Tunercats. I've also turned down the "low pulse width offset adder vs. BPW" values at around 1200uS to the same values of around 1500uS... this didn't seem to have much of an effect...

Any ideas?

 

Problem has been solved.

Due to the crappy useless underdrive pulley, I was only getting 10.8 volts at idle. Pulley has been removed and now i'm getting a much more ignition system friendly 13.3 volts at idle. I also installed my MSD 6A box.