Hey guys, on the way to work this morning i was experiencing a strange idle pattern. I started my tib up (1997 1.8l 113,350miles 5speed) and she idled around 1500, cold start, no problem. So i drive a couple miles down the road, slow to a stop light and before i know it, the car is bouncing in a pattern between 800rpm to 500rpm then back up to 800rpm all while i had stopped. It was consistent like this for 10 miles (everytime i stopped). Finally i shut the car off at a stop sign, paused for 5 seconds and restarted...no problems..idled like a rock (well for 113k)all the way to work whenever i made a stop (i travel 27 miles one way to work).

Now when the car was bouncing on the idle, there also was hesitation below 2500rpm when taking off from a dead stop. Once around 2500-3000rpm the hesitation went away. It wasn't heavy hesitation but something didn't feel right.

After i reset the car (at the stop sign) and the erratic idle stopped, so did the hesitation. Whenever i came to a stop after the reset, it idled smooth with no hesitation at all on acceleration.

The car has basic bolt ons (aos style intake, sr421 header, carsound cat, 2.25 exhaust, fidanza flywheel, CM stage1 clutch) no piggy back units, new bank1 o2 sensor, new fuel filter, no CELs, replaced plug wires (autozone brand) and spark plugs (NGK) less than 12k ago. The motor seems to consume oil (about 1 quart per 3000miles) which probably wouldn't seem so bad if i didn't put 50 miles a day on the car. 3000 comes up quick on me. I do about 1600 miles a month probably more. What do you guys think?

 

sounds like there was a sensor giving a bad reading. Once you "rebooted" the car with that restart, that fixed the sensor that was out of wack.

If it happens regularly, it may be a sign of a sensor going bad.

 

Yeah it did it again last night and the whole reset thing makes sense. Have any idea what sensor may be doing this? I wish i'd get a CEL so i could scan that sucker and run it through webtech and fix the stupid problem.

It's times like these that makes me want to sell my baby and upgrade to a '03. tongue.gif

 

if you can get access to an obd-ii cable and software you can check what sensor it is.

I would concentrate on TPS, o2 sensor, and MAF.