reving high

Post Wed Jun 21, 2006 9:09 pm

a few days ago i attempted to clean my idle control valve because of the annoying idling the car was doing.

whilst I was claening the ICV (with carb cleaner) I got excited and started to clean all the other bits which attach to the ICV.

I cleaned the rubber pipe that attachs to the ICV and also the big rubber pipe that goes into the throttle body.

Whilst I did these bits I had a quick peek into the throttol body and could see that it was quite dirty so i sprayed it with carb cleaner and gave it a wipe using a cloth i also cleaned the big butterfly thingy in it aswell..

The good news is now the cars idling doesn't go up and down like it did before (so maybe the ICV is clean now).

The bad news is the idling is significantly higher than normal, its near enough on 1600 RPM and it drops down to about 1500 RPm when the car is warm.

what have I done to cause it to idle so high?
have I accidentally adjusted the butterfly?

how can this be rectified?

Post Wed Jun 21, 2006 10:08 pm

I had the same problem when I put my car back on the road. I cleaned everything a little too much maybe and when I played around with the TB when the car was running I noticed that it was not closing fully but if I moved it by hand the extra few mm it went back to normal.

I fixed it by smearing grease all over the springs etc on the TB arm and sprayed some silcone lubricant over the mechanisms etc.
Took a while to settle in and loosen up again but its fine now.

Post Wed Jun 21, 2006 11:32 pm

Check the hose to the ICV on the engine side for air leaks, but as Adammcf says, check the silly things like the throttle not closing first.

Post Wed Jun 21, 2006 11:43 pm

I got fed up with my idle, so just adjusted the bolt on the throttlebody to make the arm constantly on a bit. Why doesnt everybody do this?

I think it much be wrong?

Post Wed Jun 21, 2006 11:53 pm

bmwe30mtech wrote:I got fed up with my idle, so just adjusted the bolt on the throttlebody to make the arm constantly on a bit. Why doesnt everybody do this? I think it much be wrong?

DON''T TOUCH THIS SCREW. It only has one correct position - the one BMW set it at!

Post Wed Jun 21, 2006 11:55 pm

Oh dear, already done, and it idles so well.

What have i done?! Not going to blow up or anything is it

Post Fri Jun 23, 2006 2:13 am

i did the same to! got carried away with the carb cleaner and cleaned the pipes,butterfly and throttle body put it back and idled at 1700rpm

adjusted the screw near the spring now idleing sweet

Post Fri Jun 23, 2006 8:49 am

ifty wrote:
adjusted the screw near the spring now idling sweet

If adjusting this screw was the sole cure for high idle speed, then someone must have miss adjusted it before!
If it hasn't been touched before, then you are deliberately introducing a second fault to mask another fault.
There is only one correct setting for this screw, and it's nothing to do with idle speed.

Post Fri Jun 23, 2006 1:23 pm

Thanks for the replies.

Cars MOT was done today and the guy at the garage said he would fix the idle problem so will see how he tackles that. hopefully he will not adjust this so called screw that brainmoore is talking about.

The car did fail on its rear brake line pipes (bcos of corrosion) this will need repairing and he was complaining about my rear red indicators, saying they should be orange instead of red

. I will have to put the original lights back in (I have a spare set so thats not a problem).

failed bits
1. rear brake lines
2. red rear indicators
3. back brake pads worn
4. reving high (i think this is just advice)
5. wiper and a couple of bulbs

The garage quoted me Ã‚£145 to supply and fit the brakelines, rear brake pads, sort out the idling and the wiper/bulbs, does this sound like a good deal?

Post Fri Jun 23, 2006 4:58 pm

Brianmoooore wrote:
ifty wrote:
adjusted the screw near the spring now idling sweet
If adjusting this screw was the sole cure for high idle speed, then someone must have miss adjusted it before!
If it hasn't been touched before, then you are deliberately introducing a second fault to mask another fault.
There is only one correct setting for this screw, and it's nothing to do with idle speed.

My car never idled, and now it does perfectly, and i think we muct be talking about different screws. Im talking about the one the swinging arm buts up against when the cable isnt pulling it. This must surely just adjust idle? As i unscrewed it, idle dropped, screwed it in, idle rose?
Also if only BMW should set it why isnt it tamper proof?
Not trying to argue at all, just realy confuses over this issue, and why local BMW didnt try it?!

Thanks Brian

Paul

Post Fri Jun 23, 2006 9:52 pm

[quote="bmwe30mtech] i think we muct be talking about different screws. Im talking about the one the swinging arm buts up against when the cable isnt pulling it. This must surely just adjust idle? As i unscrewed it, idle dropped, screwed it in, idle rose?
Paul[/quote]
Thats the screw, and it 's not an idle adjustment.
The idle should be controlled by the ECU modulating the ICV, which is plumbed in parallel with the throttle butterfly.

Post Fri Jun 23, 2006 11:16 pm

Thats the screw in was on about,the one which adjusts the swinging arm.After i cleaned the inside in the throttle body it was ideling at 1700rpm and i had a slack in the cable after adjusting all was good.

Post Sat Jun 24, 2006 3:37 pm

If that was the idle control screw ,Why would you have an idle control valve. I had the same fault after cleaning. So I disconnected the battery Left the car for a couple of hours , Reconnected and took it for a drive , right through the rev range. sorted, tickover back down to normal

HTH

john

Post Sat Jun 24, 2006 4:03 pm

I tried a new idle contol valve, cleaned them, new ALM, new pipes, the lot. Its been a motor mistery, and i had it since last august when i bought the car! I got fed up so just moved the screw to move the 'arm' slightly.

Cheers