Just purchased a '00 M Coupe to replace my BMW fix for a e39 540 I just sold.
Still learning a lot about the S52 motor. Similar systems to the 540's ( I did all my own maintenance...) but some things are completely different.
The problem:
On cold start, there is a whining noise that sounds like a fan. The idle is rough. Feals like the A/F is off due to a bad O2 or MAF. Once the whining goes away, the idle clears up and runs fine. Takes about 60 seconds or so. Is that the period to go to closed loop on the O2 sensors?
Oh, the SES light went on this morning.
There is no problem on a warm start and no whining either.
What do you recomend that I look at first?
Thanks!
Ian
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| Reply » Rough Idle Question |
If you do a search, you will see the 'rough idle' issue has been talked about before. Here is the link to a thread I once started. This could give you some ideas:
http://www.bimmerfest.com/forums/showthread.php?t=97357
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| Reply » Rough Idle Question |
Yes, thanks, I did do about 2-hrs of searching. Nothing about a fan noise though....
Sorry, just want to know what is typical for the s52 and associated ECU bits. Thought I could get some help....
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| Reply » Rough Idle Question |
Quote: Yes, thanks, I did do about 2-hrs of searching. Nothing about a fan noise though....
Sorry, just want to know what is typical for the s52 and associated ECU bits. Thought I could get some help.... | Noise for 60 seconds at startup would be the secondary air pump. It's in the compartment under the hood on the driver's side by the firewall.
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| Reply » Rough Idle Question |
OK, getting into noob teritory for me. What does the secondary pump do? I assume it has something to do with smog? It's louder then the HVAC system on highest fan speed.....
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| Reply » Rough Idle Question |
Never mind, found it.
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Rough Idle Question