M44 Idle Speed - Proper Fix!

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allisong
Joined: Sun 27 Aug, 2017 14:20
Posts: 1

  Z3 roadster 1.9

M44 Idle Speed - Proper Fix!

Post by allisong » Thu 16 Nov, 2017 10:12

My Z3 with the M44 engine (24k miles only) idles at 800 rpm (from INPA reading) and is “as usual” for these engines a bit lumpy and a little bit prone to stalling. The BMW fix for this is to retard the exhaust cam by 6 degrees, but this takes off 4 Hp and some torque. I noticed that the engine idles at 950 rpm when the DME gets a speed signal and then drops to 800 when stationary. At 950 it is very smooth.

So I took the plunge and went down to EndTuning (Enda Ward) and he extracted the DME map from my car and we could see the idle target when warm was set at 780. There are at least six idle value maps in the DME for idle values depending on temperature (1200 at -20 for instance) and depending on whether the A/C is on (increase of 20 rpm) and whether it has an auto box, etc. He revised the target idle to 950 for all the maps where it was lower than this and reflashed the DME.

Car now idles perfectly, much much better! Nothing else was changed in the mapping.

Cost £40.

Brilliant!

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Mad Max
Joined: Sun 28 Feb, 2010 11:18
Posts: 440

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Re: M44 Idle Speed - Proper Fix!

Post by Mad Max » Fri 17 Nov, 2017 12:40

Enda is brilliant, he's a walking BMW diagnostic tool. He's remapped three cars that I've owned including my current one. He's probably forgotten more about BMWs than I'll ever know!

He's diagnosed, over the phone or email, many issues I've had and saved me hundreds of pounds, if not thousands for his diagnosis and free solution to my VANOS issue alone, the solution can be viewed in the FAQ.

Top bloke and proper enthusiast. Glad someone else is using him!

handsomejackuk
Joined: Sat 18 Jun, 2016 11:35
Posts: 295

  Z3 roadster 1.9
Location: Blaenau Gwent South Wales...

Re: M44 Idle Speed - Proper Fix!

Post by handsomejackuk » Sat 18 Nov, 2017 00:10

i always wondered why the idle drops after a few seconds.... if you are coasting it stays at about 950 rpm then once the car completely stops after a few seconds it drops to abouty 800rpm..... its as though its linked to a wheel sensor or the fact the car is moving...

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