Revving up an down constantly

[Hawwy]

As title says revs up and down constantly when idle or coasting? Really annoying .

Sometimes its fine sometimes it does it outa the blue..

Cheers

[morgey]

Checked your coolant levels?

[Driver]

Potential Vac leak ?

[monty1991]

Sounds like vac leak. Mine did this when my dumpvalve vac pipe blew off.

[Hawwy]

Where do i begin in checking for vac leak dont know where to start

[pick1]

All intercooler piping all vac line etc mate

[Hawwy]

Okay mate hard job lol

[russ78]

Good place to start is between pcv valve and inlet manifold

[Liam_D]

Check your gasket between the throttle body and inlet manifold mate. Sounds silly but a slight tear in the gasket will cause it to idle funny and cut out spontaneous

[Taggy]

If its a bad leak it will sound like a hissing sound, where the intake manifold is you have loads of small pipes attached to it on the back front and right hand side, just inspect them all, shouldn't take long to find it

[Starbo Moorley]

Check all your pipes of the tb are connected or blabked off

[morgey]

Dont they say spray some brake cleaner on and around pipes n fittings and when you hear a change of engine note thats where the leak is??

[Stu]

If its hunting then its more than likely the idle up bypass under the throttle body. Its very common for them to get gunked up which causes the revving up/revving down cycle. Pull the unit off and give it a really good clean. Also make sure the water lines are clear. Will pay to keep a track of what line goes where, pretty easy to plumb the water line into a vac line by mistake.

[Hawwy]

Were is this valve mate?also i turned down idle with idle screw its idling fine but if i use wondows for instance the revs drop

And if i put headlights on revs go high

Edited November 28, 2012 by Hawwy

[micky boy]

but if i use wondows for instance the revs drop

And if i put headlights on revs go high

Thats normal!...Think Stu is on about the ICV on a N/A which are under the throttle body! but on a glanza they are on the left hand side of the inlet manifold!

[Stu]

Its been a while since I've worked on a EP91 but on EP82's and EP71's regardless of turbo or not its on the under side of the throttle body. Has water lines to it and two vac lines from the power steering.