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      05-17-2022, 11:20 PM   #1
bryanhoag
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Increase idle RPM

Does anyone know a relatively inexpensive way to permanently increase the RPM at idle?

I know Autel and Autologic tools can do this but they cost thousands of dollars.

I had my local Indy shop increase my RPM at idle because my Z4 ran a little rough idling below 700rpm. But then the dealer over-wrote the coding.

It was checked for a vacuum leak. None found.

Easiest way to get around this is to always leave the AC on. But, I'd prefer to increase the idle slightly without the AC on.

Thanks all
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      05-17-2022, 11:51 PM   #2
Marcoose
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MHD has a minimum rpm feature. Sadly I don’t remember how it works.
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      05-18-2022, 02:28 AM   #3
KennyP
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Isnt raising an idle like a temporary bandage while ignoring the underlying problem that causes ruff idle in the first place?

Reset adaptations, plugs, coils, injectors and O2 sensors are the main things to look at.

I do reset my adaptations with my Cobb accessport a few times a year. And it has made the engine run smoother etc. Good thing to do after repairs and maintenance, changing seasons and so on.
Sadly Cobb doesnt have a easy idle rpm setting. MHD i think does have that.
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Last edited by KennyP; 05-18-2022 at 02:39 AM..
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      05-18-2022, 04:09 AM   #4
bigendbob
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23i my rpm was a bit wobbly at start at idle.
My Foxwell reader showed battery capacity at 60 %.
It shows historical % charge data and hours.
Charged battery, now back to 75%. (not 100% ?).
Wobbly rpm gone.

Might be a battery problem.
How old is battery, my car battery is 6 yrs old on 12 yr old car.
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      05-18-2022, 04:11 AM   #5
bryanhoag
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Battery is less than 1 year old.
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      05-18-2022, 08:31 AM   #6
paris1
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Quote:
Originally Posted by bigendbob View Post
23i my rpm was a bit wobbly at start at idle.
My Foxwell reader showed battery capacity at 60 %.
It shows historical % charge data and hours.
Charged battery, now back to 75%. (not 100% ?).
Wobbly rpm gone.

Might be a battery problem.
How old is battery, my car battery is 6 yrs old on 12 yr old car.
Sounds like you need to consider a replacement!
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      05-18-2022, 04:34 PM   #7
bigendbob
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Well also have a brake problem, might be vacuum leak.
My battery is now 90% charge.

Foxwell reader has a section on adjusting rpm.

Last edited by bigendbob; 05-19-2022 at 01:56 PM..
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