Thread: Surging idle when warm

After a moment of rage, and a backwards burnout with the traction control on, my idle jumps from 500-2000rpm. My short term fuel trims are sitting at 128, and the pcm commanded afr is around 13.8:1. The 02 readings are around .480mv, never higher. They do not switch like they are supposed to. What I dont understand is how can the pcm be commanding a rich afr like that, but the 02 not show that? Im throwing 2 codes, maf circuit a low input, and now 02 bank 1 sensor 1 no activity. no vacuum leaks, no exhaust leaks. Ive put a new maf on, cleaned the tb, and cleaned the iac. HELP ME!

its broken hope that helps

I agree with that guy

Broken

Its a shot in the dark but id reset the pcm. Take the neg cable off for a few hours start it up and see what happens.

if the o2 isnt switching at all id look at that first. however, that shouldnt cause the idle to fluctuate like that. also, does it run better with the MAF unplugged?

Originally Posted by kfish

the wiring is all ok on the 02 nick, and yes itll hold a steady idle with the new maf unplugged even

If unplugging the MAF makes the idle/surging go away..... to me... that is your problem.

its true. some MAFs dont care, others get super wonky without it. you got one that doesn't like it.

take it apart already.

Well that rules out alot. Id imagine it to be a sensor. Time to break out the Meter and start testing.