Happened twice, i usually idle at 800-900rpm steady but it happend twice that i would idle at 1100rpm and one time it went at 2000rpm by itself, then suddenly it would go back to normal 800-900rpm. What could be wrong?

Coolant temp sensor along the exhaust side on the coolant rail. They run about $35 from the stealer.

when mine went it took out the ecu. i had a very high idle that only got higher the warmer the engine got

idle valve and related intake hoses underneath.

if you continue to let the idle hunt, it would confuse the ECU and therefore itll fry itself.

best to get that fixed!

someone told me mine idels at 1200 is because of the chip.....when you have a chip with stock intake....

i put the new intake it went down a tiny bit..... but it stays at 1000-1050

hmmm? car died on Saturday night, battery is completely dead, just had alternator removed, voltage regulator is probably bad one side is shiny other is not, just went to local parts shop had alternator check twice and its okay. as soon as i get home after work i will reinstall. I have slight mods evo air box, borla exhaust, dinan chip, and magnacor wires. Man i hate when stuff like this happens

My idle did that a couple of years ago and it was the idle valve. When you say that the car died, was it just all of a sudden or after the car had been sitting and then trying to start it?

it died due to no battery power, i just replaced my voltage regulater and full charged my battery, cleaned out the engine bay, double checked here and there, now the car runs solid, haven't had the idle go high or low constant steady idle at 900 rpm. I guess it was just a faulty voltage regulater. i replaced my ECU 6 years ago.

it died due to no battery power, i just replaced my voltage regulater and full charged my battery, cleaned out the engine bay, double checked here and there, now the car runs solid, haven't had the idle go high or low constant steady idle at 900 rpm. I guess it was just a faulty voltage regulater. i replaced my ECU 6 years ago.
Cool, glad you got it running.

thanks, now i need to send it back to the body shop for a repolish and take out some weird spots.

do m20 have throtle position sensors?

it died due to no battery power, i just replaced my voltage regulater and full charged my battery, cleaned out the engine bay, double checked here and there, now the car runs solid, haven't had the idle go high or low constant steady idle at 900 rpm. I guess it was just a faulty voltage regulater. i replaced my ECU 6 years ago.
you know i would never really think about the voltage reg. it could be that.....i guess even tho my battery is fully charged