cleaning the iacv on turbo

[danjama]

Any guides/tips for cleaning Idle control valve on mk2 turbo? Hoping it will sort my idle issues. Is it as easy as it looks or will something catch me out?

[stuMR2lee]

For an NA but similar enough to get an idea. Turbo large gasket is metal so should be fine: http://mr2oc.co.uk/ocforum/viewtopic.php?t=141257

[Peter Gidden]

You'll probably find the 4 screws tricky to get undone unless someone has done them before.

You'll need a new ISC to TB gasket from Toyota.

Don't go poking things in the ISC itself. It's precision ground to fit the body. Just use carb. cleaner, a few cotton buds and an airline to blow everything clean.

[stuMR2lee]

I find the 4 screws can usually be successfully removed with an impact driver and correctly fitting bit. Light tap with a hammer and the twisting motion helps undo them.

[danjama]

Thanks all seems easy enough then, will be careful of those four screws

[jimGTS]

Some info on the iscv and cleaning in my project thread here

http://www.imoc.co.uk/forums/viewtopic. ... c&start=60

[danjama]

Thanks jim, very helpful

Think i'll have a look on rinkya for a gauge as well

[danjama]

Right, so i cleaned out the valve with carb cleaner and it's made no difference to my idle issue. The symptoms are:

- low idle on cold start, stalls if i prod the throttle sitting in neutral
- will drive fine in gear but then stall when i go in to neutral (say for lights or give way etc)
- runs absolutely fine after about 3 minutes of driving, except warm idle will fluctuate between 900rpm and 1100rpm depending on how it feels.
- Note the idle does not HUNT up and down the revs. If i stop at one set of lights it may idle at 900, and then if i stop at the next set it may decide to idle at 1100
- Sometimes it will warm idle just fine
- cold idle is always as above

My old turbo would cold idle at 1250-1400 and warm idle at 900, which I believe is perfect. I just want this one to do the same!

Please help, how do I narrow this down? There's no fault codes.

edit to add - fuel economy is also slightly worse than my old turbo rev 2, and that was lightly modified.

[danjama]

Pretty much similar to symptoms described here

http://www.mr2oc.co.uk/forums/41/160522.html

[Peter Gidden]

Start by checking ignition timing. You'll need a timing gun and bridge TE1 and E1.

[danjama]

I don't have a timing gun Peter but thank you. Is there anything else I can try? If I unplug the cold start injector switch should the idle change? How about any of the other relevant sensors?

[danjama]

The car also has traction control, i don't know if that makes any difference!

[Peter Gidden]

I don't have a timing gun Peter but thank you.

Well timing has a big effect on idle speed so suggest you get hold of one.