intermittent 'check engine'

Hi,

I've been seeing an intermittent 'check engine' light in my 1992 900 (NA). I read the code (I'm getting rather practiced at reading codes these days) from the LH control unit. There were two stored:

  1. "oxygen sensor self-compensating circuit problem (incorrext air-fuel ratio while driving)"

  1. "air-fuel mixture too lean"

Ok, so I'm thinking there must be an air leak somewhere, despite the fact that I just recently replaced most of the vacuum hoses. The trouble is that the warning light only comes on intermittently, and only when driving at highway speeds for at least 10 or so minutes. Also, the engine still seems to run ok when this is going on. So how can I figure this out?

Thanks, John

Reply to
John B
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Mine '93 9000 CS has been going on and off ever since I got it. You hear tales of new oxygen sensors or even loose fuel caps... I've just ignored mine and it's and it still had an engine under the hood last time I checked :)

Reply to
Nasty Bob

My 1991 900i has that light on since I bought it 6 months ago. It starts and runs and everything seems to work OK. When I complained at the garage, the mechanic said it was difficult to trace exactly why the light comes on, and he offered to take the bulb out if that would make me feel at ease... Just make sure there's enough oil and water and keep driving it until a real problem shows itself.

Reply to
MH

John sounds like your air mass meter. If its original it probably needs a new one. they are expensive like 500 bucks but you can buy rebuikt for 175 saab site .com . best regards papa

Reply to
PAPAGENE4JACK

Yes, that had occurred to me. Thanks for the suggestion.

John

Reply to
John B

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