2.0 high idle speed

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Jfgoldfish
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2.0 high idle speed

Post by Jfgoldfish » Fri Feb 14, 2020 5:40 pm

I have noticed my zed idles at a fairly high speed. Is 900 - 950 rpm normal when hot?
If not what might be causing it to idle high? Vacuum leak?
I plan to replace the vanos solenoid seals that are seeping a tiny bit of oil since they were removed for cleaning. Would the inner oring passing oil cause high idle?
The vacuum pump is also needing seal replacement, doubt these could be related?
Thanks all. Hope you are enjoying your valentine's this evening :wink:
2006 Z4 2.0i Ruby Black

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colb
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2.0 high idle speed

Post by colb » Fri Feb 14, 2020 7:19 pm

Yes, check for air leaks, inspect all rubber componants from Maf onwards for splits or holes, smoke test would find any that you have if you know someone that can do this. Also worth cleaning the idle control valve, they can get gummed up and stick resulting in high or bad running at idle. Where are you located, I have a smoke machine but being in South Wales I may be too far away.
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Jfgoldfish
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2.0 high idle speed

Post by Jfgoldfish » Fri Feb 14, 2020 9:43 pm

colb wrote:
Fri Feb 14, 2020 7:19 pm
Where are you located
I am in Northampton so a trip to Wales may be too far. Although if it's still playing up by summer time it may be worth the drive, Wales is a beautiful place.

I didn't know these engines had an idle control circuit. Is the valve easily accessible? I will give it a clean tomorrow if storm Denis doesn't ruin my plans!
2006 Z4 2.0i Ruby Black

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ph001
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2.0 high idle speed

Post by ph001 » Fri Feb 14, 2020 11:27 pm

No, your car does not have idle control valve. I would try valvetronic reset as a first stab (do a search on here).
2007 E85 Z4 3.0Si manual :driving:
19" CSL's | Eibach Springs | Aeroskirts | Z4M front bumper | Clear brake light | ZHP | RCH+| Stubby

2004 E46 M3 coupe manual - gone but not forgotten.

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Jfgoldfish
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2.0 high idle speed

Post by Jfgoldfish » Sat Feb 15, 2020 12:47 am

ph001 wrote:
Fri Feb 14, 2020 11:27 pm
I would try valvetronic
Thanks ph001,
I will have a read tomorrow and give it a go. 👍
2006 Z4 2.0i Ruby Black

Jfgoldfish
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2.0 high idle speed

Post by Jfgoldfish » Sat Feb 15, 2020 5:11 pm

So I replaced the o-rings on both vanos solenoids and vacuum pump today whilst storm Denis kindly spat on me!
The idle is smoother, probably due to the solenoid cleaning. They might be getting a bit worn at nearly 100k. When do they normally end up needing replacement?
I did try the valvetronic reset that involves pumping the throttle after turning the ignition on. This might have helped a little, hard to tell.
The real idle is actually 850rpm read with a scan tool. The rev counter over reads just a fraction (around 50-75 rpm). what should the idle actually be? 850 sounds more in the right region to me.
Plan is to pick up a K-LINE cable in the near future to get some better diagnostic data and properly rest some of the adaptations.
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ph001
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2.0 high idle speed

Post by ph001 » Sat Feb 15, 2020 8:18 pm

Jfgoldfish wrote:
Sat Feb 15, 2020 5:11 pm
I did try the valvetronic reset that involves pumping the throttle after turning the ignition on. This might have helped a little, hard to tell.
That just rests the throttle adaptations. The valvetronic reset has to be done through INPA etc.
2007 E85 Z4 3.0Si manual :driving:
19" CSL's | Eibach Springs | Aeroskirts | Z4M front bumper | Clear brake light | ZHP | RCH+| Stubby

2004 E46 M3 coupe manual - gone but not forgotten.

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Jfgoldfish
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2.0 high idle speed

Post by Jfgoldfish » Sat Feb 15, 2020 8:51 pm

ph001 wrote:
Sat Feb 15, 2020 8:18 pm
That just rests the throttle adaptations.
I suspected that that might be the case. There is some seriously contradicting and misleading info floating around on the subject. I will grab an OBD to USB cable from bcables or similar and see how i get on.
Thanks again for the advice ph001. :)
2006 Z4 2.0i Ruby Black

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