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DISCUSSION => Engine + Driveline => Topic started by: JHZR2 on March 11, 2012, 08:54:44 PM

Title: E30 M42 Cold Start - raised idle
Post by: JHZR2 on March 11, 2012, 08:54:44 PM: Does anyone with an E30 M42 engine get a raised idle at cold start?

Some of my cars do 1000-1500 rpm for a short while when it is a very cold start. My 318i always starts and runs at the same idle speed it does any other time. It is a bit low - 550 or so on the tach, but it is consistent and smooth.

Does anyone have a fast idle at cold start that comes down to normal after?
Title: E30 M42 Cold Start - raised idle
Post by: carguy101 on March 20, 2012, 07:55:49 AM: My guess is it is running rich and trying to pump the oil through the engine before driving. most cars run rich on start up but this is my guess.
Title: E30 M42 Cold Start - raised idle
Post by: Gabs on March 20, 2012, 08:19:37 AM: Living in Canada I drove my car through a couple winters and experienced the idle around 1300 on cold starts and once warm it usually settled down around 800. It doesn't sound that abnormal, but I would clean the Idle Control Valve just for good measure, it may be sticky.

This little guy.
(http://www.esatclear.ie/~bpurcell/icv3.jpg)
Title: E30 M42 Cold Start - raised idle
Post by: Geoff on March 20, 2012, 12:15:05 PM: I'm thinking a slightly raised idle in cold weather is normal also. Mine will run at around 950 / 1000 rpm on a very cold morning, coming down to a normal 750 or so after 3 or 4 minutes.
Geoff
Title: E30 M42 Cold Start - raised idle
Post by: Gabs on March 21, 2012, 08:16:21 AM: For reference how cold of a morning are you referring to Geoff? My very cold morning are around -25f give or take.
Title: E30 M42 Cold Start - raised idle
Post by: Geoff on March 21, 2012, 02:44:50 PM: cold around here is anything below freezing, 32F or so. anything above that, and the idle settles at 750rpms right away.
Geoff