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Old Nov 20, 2003 | 07:55 PM
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Had a new clutch fitted today to my p1, i didn't pick it up till late afternoon, started the p1 up and all was fine on cold start tickover, however by the time i had got the car home the tickover was going from 1000rpm to nearly stalling, although i'm taking the p1 back tomorrow i was wondering if you technical lads or lasses might have a clue, don't want the bloke to give me any bull when i go back tomorrow
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Old Nov 20, 2003 | 08:50 PM
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MAF sensor..

Whilst the clutch was changed they disconnected the battery.. this reset the ecu and erased it's learnt memory which had slowly compensated for a dying MAF sensor..

Drive it off boost until it is checked at the garage.. but I suspect MAF..

JGM
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Old Nov 20, 2003 | 11:25 PM
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Just bought a MY97 that seems intent on stalling, once warm. Is this likely to be a similar problem?

(sorry for piggy backing, first post an all!)
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Old Nov 20, 2003 | 11:28 PM
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More than likely yes..

Erratic tickover and stalling is a symphtom of the MAF failing.. although it could be other things of course.. but MAF is most likely..

JGM
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Old Nov 20, 2003 | 11:31 PM
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Thanks!...and for the quick reply!!
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Old Nov 20, 2003 | 11:33 PM
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no worries..

Not sure if you can for the 97 but you can get the MAF sensor separate to the housing on the newer cars I think.. makes it cheaper..

JGM
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Old Nov 20, 2003 | 11:35 PM
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...is it gonna cost a fortune then?
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Old Nov 20, 2003 | 11:35 PM
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From: Bournemouth - 5x Ex Impreza owner. 997 GT3 CS.
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On a 97 it might be an 02 sensor. MAF's were a bit better on 97.

MB
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Old Nov 20, 2003 | 11:39 PM
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...to be honest I haven't got a clue what were talking about!
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Old Nov 21, 2003 | 12:33 AM
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...sorry...anyone care to explain to the poor ignorant fool what a MAF unit is?
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Old Nov 21, 2003 | 10:36 AM
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From: oustide the asylum?
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MAF sensor = mass air flow sensor.

It sits in the inlet pipe, just after the airbox and measures the air going into the engine.

On the early cars this is a hot wire that gets cooled down by the air. The required current to bring it back up to a set temperature gives an indication of airflow.
On later cars, this was replaced with some kind of film sensor - I've never needed to know how these work!
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Old Nov 21, 2003 | 11:52 AM
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From: Bournemouth - 5x Ex Impreza owner. 997 GT3 CS.
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As the man says, look for you air box on the left side of the engine bay. Theres a 4" diamater black plastic tube coming out of it. The MAF sensor lives in there. Theres a plug going into the side of it which takes the signal to the ECU.

02 or lambda sensor is in the exhaust downpipe. Look for the turbo, at the back of the engine bay, with a silver heatshield over it. The outlet pipe from that goes down under the car, which is the downpipe. Screwed into the right hand side of that, sticking out about 2", is the sensor. Its easy to replace, and probably a good thing to do every 20k miles or so. They are very unreliable. Either of these failing will give bad idle, and may net give you a CEL (check engine light)

Do a search.

MB

[Edited by Dark Blue Mark - 11/21/2003 11:52:42 AM]
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Old Nov 21, 2003 | 04:17 PM
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Thanks for the replies lads, it was the maf sensor, running like a dream again now, thank ****
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Old Nov 21, 2003 | 04:47 PM
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Excellent.. glad you sorted it.

JGM
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Old Nov 21, 2003 | 06:34 PM
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...thanks for the info gents!
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