Idle screw?

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bpowell555
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Mon Nov 16, 2009 11:53 pm

I thought you couldn't adjust idle but this seems to suggest otherwise. I'd raise mine a bit as its too weak from cold, revs prone to nearly dying....
Setting the idle

The butterfly valve on the throttle body is normally fully closed. The idle stop screw needs to be adjusted, so the butterfly valve is slightly open. Getting the right adjustment requires trial and error (and a warmed up engine). You want the idle to be around 700rpm, and the MAP sensor to show the lowest possible value. However, I found that 700rpm idle was too low for cold starts, and set the idle a bit higher. Make sure the timing is set to 16 Degrees when idling (there is a setting that can override the timing to this when there is no throttle).
Be careful when turning the idle screw. Its probably never been moved since manufacture, and is easily broken (I know from experience!). Use penetrating oil first.
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gareth
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Tue Nov 17, 2009 12:06 am

megasquirt doesn't use an idle control valve does it?

you cannot adjust the idle on a 325i, the ICV does it for you. anything you do with that screw is messing with it's ability to work properly. if you open the butterly, the icv will close to compensate

if it's not idling correctly, fix the problem not the symptom. check the hoses for cracks, check the blue temp sender (does it run rich / splutter?), check the TPS setting and function, check the TPS
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Brianmoooore
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Tue Nov 17, 2009 9:19 am

THERE IS NO IDLE ADJUSTMENT SCREW ON A E30!!!!
If your idle speed is low, find out what's actually wrong with your car and fix it!
tez180
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Tue Nov 17, 2009 9:33 am

I haven't been here long - but I have seen Brian post that at least 20 times.
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beamer-boi
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Tue Nov 17, 2009 12:55 pm

Brianmoooore wrote:THERE IS NO IDLE ADJUSTMENT SCREW ON A E30!!!!
If your idle speed is low, find out what's actually wrong with your car and fix it!
i thought the screw on the air box to adjust air mix adjusts the idling aswell?
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toby
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Tue Nov 17, 2009 3:32 pm

The screw on the air box doesn't adjust the idle speed directly, just the mixture of air to fuel.
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stonesie
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Tue Nov 17, 2009 3:44 pm

toby wrote:The screw on the air box doesn't adjust the idle speed directly, just the mixture of air to fuel.

Don't just go playing with this at random, get it to your local MOT station and get them to adjust it with the gas analyzer, they shouldn't charge much as it won't take them long...
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beamer-boi
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Tue Nov 17, 2009 5:14 pm

oh right ive already messed with the screw woops my bad lol
asmith88
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Tue Nov 17, 2009 7:54 pm

as above get a professional when dealing with them , normally just best leaving them be
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