Diavolo

my idle jumps from 1000rpms to 1500rpms then falls to 1000, then back 1500 continually. The car is an 87 non-turbo.

im not the best mechanic, but ive inspected all the vacuum lines and a friend (who is a mechanic) took a look at it too, but we couldnt seem to figure out what is causing the problem. He disconnected the IAC to see if it would have any effect but nothing changed.

Anyone experience this before? or have any idea what could be causing this?


thanks in advance for your replies.
-Diavolo

1987RX7guy

iTrader: (3)

Check your TPS

Santiago

jgrts20

yea check ur TPS that might be the prob!!

Diavolo

if its not the TPS, any other ideas?

1987RX7guy

iTrader: (3)

Well from when I took off my exhaust and ran only headers I know that little or no restriction there will increase the idle of a car. So one of the possible contributers could be an exhaust leak. Another could be a small intermitent vaccume leak that is caused by heat and/or cold. But the jumpy idle is 90% of the time your TPS. It may be either bad or need adjusting.

Santiago

Diavolo

ok thanx. i dont think its a vacuum leak, and i hope its not the TPS. Im only running one cat, the others are gutted, could it be a problem with the ports?

Lastly i washed the car right before it started doing this, and a little water got inside the engine bay, could it have shorted something out?

i was sitting at a stop light when this began to happen.

jgrts20

have u change ur fuel filter lately cos it might be plugged or very dirty which could cause a non-even flow of fuel to ur engine!! the idle didnt change on me when i replaced the exhaust so i dont think it has anything to do with that!! could also be a leak in exhaust or the hollowed out CATs!! but check the TPS first!!