c20let high idle problem

[torquey]

My c20let starts idiling from cold at 1200 rpm and then starts climbing to.near 2000rpm and wont go down I've checked everything. I've noticed its smoking straight away from cold and the wideband is all over the place.The only thing I can think it is is the cts sensor any help would be great its really peeing me off now.:mad:

[nova_stee]

Air leak by sounds of it after throttle body

[torquey]

I've checked for air leaks had all the vac pipes off and boost pipes New gaskets on its got me stumped! I've sprayed around the pipes no change in revs just constantly idling at 2000 rpm.

[torquey]

Any one shed some light !!!

[torquey]

Bttt

[meritlover]

electrically disconnect the ICV. If the revs drop it could be an indication its been asked to open (perhaps by CTS failure) if you clamp the hose or block it off and the revs are still high then that would suggest an air leak. The lambda being all over the shop would point towards unmetered air, ie- a leak downstream of the AFM

[torquey]

Ive tried that mate no different being unplugged i did squeeze the icv hose and the revs droppe. Ive now removed the loom and going to go through it for snapped wires so fingers crossed thanks.

[torquey]

Right ive found a few dodgy wires repaired them put loom back in still doing it. I've got another icv to try so will give that a go tonight its really doing my head in now anything else I could check??

[paul burney]

Let me no how you get on mate I have the same problem

[torquey]

Will do mate how long has yours bein playing up??

[paul burney]

Since I had put it in we through a stage of reving up to 3k then back down to 1k when warm I swiped the icv now it's just at 2k when warm starts off at 1k when cold just like Urs then Climbs

[torquey]

Yeh its very annoying as mines had that many new parts. Gonna try another new cts ans see from there .

[paul burney]

Ano it's a joke if I sort mine al let u no

[torquey]

Yeh nice one cheers

[torquey]

Hi all this is still ongoing. I've bought a new cts fitted it today and still the same. Ive checked the wiring to the cts all is good. As soon as I start it the car smokes smells like running rich and idles at 2000 rpm and engine gets hot quickly as in gets to over half way in no time. What could ne causing this ?? Iam wanting to use the car .

[matthew172]

it will be the icv and the only way of curing it is to buy a new bosch one from autovaux

[torquey]

Don't think it is I've tried two known working ones not made any difference I thought the tps or afm??

[torquey]

Anyone any ideas??

[meritlover]

Yes ive had a few.

[torquey]

Yes mate I tried what you said when I squeezed the icv pipe the revs dropped also disconnected it it was the same.

[meritlover]

you should bell-out the wires between the ICV and the ECU. especially if replacing sensors made no difference.

i wrote up a good test for ICVs somewhere on here before. it was quite elaborate yet very simple so i wont go into it again. Search should help though.

[torquey]

Ok will search for it and give it ago thanks for the help .

[MattBrown]

It will be the AFM.

Had this on 4 c20lets now, almost bet my bottom dolar on it.

Starts fine, then sits between 1700-2300 rpm at idle.

Try a spare one mate :thumb:

[torquey]

I've ordered a new afm will give it ago when I get it cheers

[paul burney]

Have you tried the new afm yet mate intrested to see how u get on

[torquey]

Got on coming tomorrow mate will.report back fingers crossed

[paul burney]

Haha good luck

[dudley]

Have you checked boost pipes to the intercooler ?

[torquey]

Have checked every pipe mate no problems there I've tried a new afm problem still there. Could the icv be the problem? Starts fine then.instantly rises to 2000 rpm.

[meritlover]

Have you tested the ICV?

[torquey]

That's what iam doing tomorrow mate couldnt find your thread on here though?

[Jeff16v]

On mine, all the idle issues were damaged wires. I ended up stripping the cover off the loom and repairing loads of snapped wires. You haven't got the knock and idle connectors round the wrong way have you?

[torquey]

No mate defo right way round red-knock icv-black. I have also had the loom out stripped it all and found a few dodgy wires so repaired them still have the same problem. It's really annoying me!

[Jeff16v]

I also had to repair the mini loom connector for the icv and knock sensor, I got rifmofmthe connector in the end and went for straight wires. The connector above the throttle vac and vent valve pipes also caused high idle.

The only way to prove the loom is 100% is the continuity test each wire from the ecu plug to each connector, I know it's a cow of a job but this was the only way I could find all faults with the loom. Do you have a multimeter?

What does the idle do if you unplug the icv?

Have you still got the mini loom connector in place or has someone replaced it with connectors?

[torquey]

My loom hasn't got the mini loom its a later one its all in one with rest of loom. Gonna try with it unplugged tomorrow and see what happens even thought of getting a new loom !

[matthew172]

as said before it will be the icv, buy a new genuine one and that will sort it

[torquey]

Right I unsure though. Want to be sure as don't want to keep buying parts which don't solve the problem. Been out today went to start it straight away idle shot up to 2000 rpm where it stays no matter what I do! It's got.me completey stumped.

[torquey]

Anyone shed some light on this ??