like the title says, what causes it, and how can u fix it. my car 96 eclipse rs a/t doesnt exactly stall, but it picks certain days when it wants to try and stall, it does it when i start to go, and am in 1st, and left off the gas to quick, or if im coming to a stop, rpms will drop to about 100, and catch it self and surge up and drop back down a little, and will stay about 2 lines up from 0, about 200 rpsm. somedays when im coming to a stop light or sign, it will just surge a little down real low then go up a little and stay about 600-700 rpms and then gradually decrease in rpms til it gets to about 200, and i will normally just tap the gas or turn the wheel a little, and it will go back up, or puttin it in neutral will bring it up some too, and this is all while im stopped. it will also try and stall if im stopped and hold the gas steady at about 1000 rpms, and let off it, it will drop will low, but it wont stall. does anyone know what this could be, its drivin me insane

do you have an engine light? if not check for any vaccum leaks.

the only cel i get is 21, for the o2 heater circuit or sumthin

That could be your problem right there. I would fix that any way.

i already tried, last year around november the code came on so i bought a universal o2 sensor from auto zone, put it on, and the code never went away. tried gettin auto zone to erase it but it would still come back on, even now, i just ignore it. cel 21 is problem with upstream oxygen sensor signal circuit. sensor voltage to computer not fluctuating, what does that mean? and when i use a code checker it also gives me code p0135 i beleieve, which is upstream heated 02 sensor heater circuit fault, what is that?

my o2 sensor went out threw the code and didnt start srewing with my idle until way later, replaced the o2 sensor = fixed. that might not work for you though cause it was like that from the start? check the wiring.


I figure since I cant stop fixing the damn thing, I'll just create more problems to work on. :) The stock pile has begun. Parts PArts PARts PARTs PARTS!!!
I'm a novice listen to what I say and make your own conclusion. If I'm wrong tell me and I will learn. Thanks be to the 2gnt Gods may they grant me turbo and fruits of the Earth. Amen.

today i was driving, and started goin down a hill, so i put it in neutral, and the rpms droped to about 100 or less, no joke, but it didnt stall, it just caught itself and stayed idling really low. and if i turn on the a/c and turn it off, it does the same exact thing, rpms drop really low. does this help anyone figure out whats wrong

i checked my vacuum today, and it stayed at a steady 16, and when i gace it gas, it would drop down for a quick second, go up to about 20-21, and when i let off the gas it would drop down low, then back to 16, i tried it a couple times, and it kept tryin to stall till it finally did, any ideas?