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Hi and welcome. Can you tell me about were the noise is coming from?
Noise quite hard to pinpoint but would say from somewhere at the back of engine ,but only makes noise when driving and at certain revs (TURBO GUAGE NEEDLE BETWEEN WHITE/ORANGE) . No noise when engine rev when stationary, only in motion and underload.Also noise only starts when engine warms up
It sounds like the catalytic converter. Sometimes the insides will begin to come apart and will only happen after cat is very hot and when the turbo kicks in you are getting an extra push of exhaust plus any bleed off from waste gate. The only fix here would be to replace it.If you need more helplet me know.
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Thanks for your reply. Just to clarify, would this problem keep putting the engine management warning light on? If so, I will suggest this to my local garage when it goes in for another diagnostic check on 14/04/2010.
Brian. Also is there any way of proving this other than replacing it and hoping for the best?
No unfortuatly not. You may have to wait till it gets more frequent because pinpointing the problem.
Hi Brian ,just for info I found my problem with saab was a vacuum hose was perished and came off. Have replaced all tubes for new .
glad you found the problem