engine rev itself up and down while car stand still

[Fly-Rice]

I had ther same problem, cleaned my throttle and it was fix.

[subie]

I had ther same problem, cleaned my throttle and it was fix.

but mine is twin carb

[Latino CRX]

had same prob while ago all i done was controlled the air intake screw soo it wasnt suckin heaps of air .. been told wen the revs play up like that .. that ur car is suckin more air then it should be so try lowering down the air intake see how that goes .

[5thgen_prel]

had same prob while ago all i done was controlled the air intake screw soo it wasnt suckin heaps of air .. been told wen the revs play up like that .. that ur car is suckin more air then it should be so try lowering down the air intake see how that goes

^^^^how do u do tat??

[Latino CRX]

there should be a screw lookin thing around the throttle body which controls the air intake use a flat head screw driver and wind down

[EDracer]

i know in fuel injection cars this is caused by the stepper motor. this is a little solinoid that changes the engine revs when there is abnormal drain on engine (ie air con) cause the iar takes power from the motor the stepper motor ups the revs to compensate. because it is a carby motor, i would check the vacume lines. there is one from the brake booster to the intake plenum and there should be a "one way" valve there too, check all these are working ok and are not blocked.
i would also do an ECU reset. disconnect the battery, unplug the ECU (located under the passenger side foot kick pannel, under the carpet there is a zinc coated pannel, ECU under this.) leave the ECu out for 3-5 mins, plug back in, plug in battery and start car. let it idl for about 15 mins and turn the car off. after that take it for a drive and get up to temp. see if it is doing it still.

[nikiol22]

Civic EK1 2000 CXI

i got the same problem with the car reving itself when its in neutral. Heres the story:

I left my car undriven for around 2-3weeks, uninstalled my rsm, tacho, amp + subwoofer and neon lights. As it hasnt been driven for so long so the battery is flat. I recharged it and took it for a short drive around the streets and when it in neutral i realised the engine reving itselfs. Why does this happen?
What do i need to do to fix this? Or theres nothing i can do other than taking it to machenic and cost me heapps to fix?
PLEASE HELP!

[beeza]

^^ Answered in your thread.

No need to ask twice

[nikiol22]

i reset the ecu and the problem still happens.
cant find the screw at the throttle body

[beeza]

Check ya other thread Yo!

[aznalex]

unsure if this will help
but i had a 95 eunos 30x automatic before with your problem
revving strangely at idle

turned out to be an alternator + spark plugs combination which was stuffing up revs