Not idling right on start up.

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etxp
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Mon May 14, 2007 11:40 pm

When i start my car up, it never really idles right, sumtimes it does sumtimes it doesnt, but most of the time it nearly cuts out, then revs up again, then nearly cuts out, then revs up again, and so on. and sumtimes when im driving, and cuming up to a junction when im coming to a stop and have the clutch pressed it nearly cuts out to.
i changed the fuel pump as i had one spare and the one that was in car was quite noisy, but this did not effect the idling.
i was thinking possible air flow meter???? i cud be wrong any help appreciated.
Cheers
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etxp
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Tue May 15, 2007 12:04 am

sorry forgot to put in its an M40 1.8 :mad:
Chris-W
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Tue May 15, 2007 8:08 am

Check the rubber boot from your AFM to throttle body for cracks / splits.
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tezk
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Tue May 15, 2007 8:16 am

Sounds very much like a vacuum leak.
If there are no tears in the air elbow (usual cause) check the oil filler cap and dipstick are sealing correctly.
Then check all the smaller hoses.
Then you can check the gaskets - either listen for whistling or spray carb cleaner when she's running and see if the idle improves any.
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DaveD
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Tue May 15, 2007 10:11 am

and clean out your icv..
Morat
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Tue May 15, 2007 10:36 am

All the above are good points, one to add. If you have old/oily plugs (like me) then you'll get this idle as well. It could be worth whipping the plugs out to see what state they are in. My car has an M20 but I don't see why it would be different for an M40...
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etxp
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Tue May 15, 2007 10:55 pm

cheers guys will do this at weekend.
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etxp
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Wed May 16, 2007 11:00 pm

forgot to mention this only happens when the car is cold, havent had a chance to check anything, as the weather is miserable. and dont have garage.
DaveD
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Wed May 16, 2007 11:58 pm

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