Dear Porsche fanatics: need some feedback regarding my 1999 Porsche 911 Carrera Coupe. -Please take a look at the attached video I need some help figuring out some strange noises coming from my engine. At engine start I get a strange sound - kind of like a rattle - right at the very beginning, about this 10 second mark ; does anyone know what this means? Oil and coolant levels are good. -Around the 1 minute 53 second mark of the video you�ll notice that a buzzing noise stops, does anyone know what this means? The buzzing is from a cold start and lasts about a minute and appears to come from a unit on the left side of the engine - I touched the buzzing unit with my hand at the 46 second mark. The buzzing goes on and off again about the 2 minute 15 second mark. -Also, I do have about 10 seconds of engine ticking at the cold start that seems to be pretty normal since the oil needs to be circulated. Ticking goes away quickly but it�s there. Is there anything I should be worried about here? Thanks!
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YOUR RESEARCH1999 996 coupe engine noises - video
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The buzzing noise is from the Secondary Air Injection unit. That is normal for it to make noise upon cold start. It is an emissions thing. If it is overly noisy, it may need replacement and can be rebuilt. Ticking may be indicative of a stuck hydraulic lifter?
I don't see the video, but a rattle right after startup is not uncommon as the tensioners...um...tension. If yours subsides after about 5 seconds, I believe you're describing the sound my M96-powered cars have both made. I can't say that it's harmless - but my Boxster did it the whole time I owned it, and so does my 996.
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