I have an auto 97 with 64k on my engine.Sometimes when my car is at a stop light, waiting to turn green, the rpm drop from 750 to 250 for like 3-4 seconds and goes back to 750. It happens in drive, Park, reverse, neutral,everything. but it only happens when im not pressing the gas. This dont happen eveytime, just sometimes while waiting for the light, it will drop. What you guys think is the problem? Thanks

 

Have you done any engine mods recently, sometimes people forget to reset the ECU afterwards and that tends to cause idle issues.

Check your Throttle Positioning Sensor, this has happened to a couple people on here before, and it has turned out to be the TPS. Check webtech for the guide, and check this sub-forum to find the other poeple with the problem. I know there was a few threads on it.

 

I have an AEM CAI, 2.5 exhaust. I did reset it so, i doubt thats the problem. How do You check the TPS? What are you looking for when checking?

 

I couldn't find anything on webtech, but this thread talks about it. Run a search on the forums and you'll find a couple

http://www.rdtiburon.com//index.php?name=F...light=tps#15832

 

it is more than likely the TPS.. I have been suffering off and on with mine for 30,000 miles. Usually it is just a hunting idle.. jumping from 700 to 2 grand and back a few times and then settling out... this morning though, I brought the car to a halt before turning so traffic could pass.. and for the first time in 103,000 miles.. it stalled.

 

i had a bad day. I was in Autoshop and wanted to reset my ecu to see if that would work. I took off the battery and steped on the brake for a few seconds. then i put back the battery and the car wouldnt start, it was a clicking sound. CAar was dead. Then my friend gave me a jump and you know what he did? he reverse the positive and negative on his terminal. Mine was correct aNd the battery started to caught fire. he ripped the jumpers off and blew off the fire. The negative line, in my car, was burnt to a toast and blew a 100amp fuse. A chunk of the battery top was gone. well i ended up buying a new negative line top connector and stole the fuse off of a celica i was working on in class. Well that was my jacked up day.

anyways..... is there any thing i should know before taking off the TPS and try cleaning it? Any tips?

 

OMFG!!!

that totally sucks..... but unfortunately, i laughed while reading it... lol.gif

good luck w/ the TPS...

and do us all a favor and kick your "friend" in the nuts for doing something that stupid to your car!

 

PLEASE tell me your friend is not in Autoshop too...

I never let anyone put jumpers on my/their car. I will do it myself.

 

haha... im glad u guys enjoy the tragic story. yea hes in auto shop but im in advance auto and hes in begining auto. He is not that dumb.. he knows pretty dam much. its a just a stupid mistake... very stupid mistake.

 

Riddle me this... In addition to the floating idle, does your car have good days and bad days, performance wise? Like, does one day it feel like a rocket and the next a soggy wet noodle? If so, I'm calling our your coil packs/plugs/wires. Also, check the idle bypass circuit for leaks.