My 996 Turbo Engine keeps stalling at low revs???

I just bought a new sports car. It is a 911 996 turbo. By far the best car I've ever driven in my life. I bought it from a private garage. Before the purchase I phoned the Porsche garage to confirm its history with them. They said it was well looked after and had a lot of money spent on it. Anyway! I drove it back home and noticed that when I came to some junctions it was stalling??? It's doing it more frequent now. And I'm starting to get scared with this issue. Every time it revs by its self with no foot on the pedal it kicks and then drops below one thousand rpm then continues to stay there and sometimes it just goes (stalls) Any idea what this could be?

Tiptronic?

The wife's cabrio was doing exactly the same thing. It eventually developed into an occasional misfire. New coil packs sorted it. Pete

My money would be on MAF or coil packs.

Would be best to get this vehicle plugged into a diagnostics, if you are anywhere near our workshop you are welcome to pop over and we will stick it on the machine and check it out. Regards Martin

I'd agree that it's possible MAF or coil packs. However, agree that it needs to be diag'd as it could be a problem with the throttle housing.

Or the brake servo sticking. I had this problem on my old 996, the brake servo would stick or keep traveling after you took your foot off, therefore cutting power just as you would pull off stalling the car. Camtune recognised the problem straight away, new part fitted and problem solved...

Does anyone know how expensive this would be? Thanks to all who replied with their Porsche knowledge. Regards Andrew

Andrew, There is no way of knowing what cost is involved as the problem hasn't been identified yet. What you need to do is get in plugged in and read any fault codes out, if none it requires data logging to see what's happening. Regards Martin

Hi Andrew, you haven't mentioned if it's a manual or tiptronic car? A coil pack or faulty MAF would throw a Check Engine Light either permanently or temporarily. If the car is stalling and it's a Tiptronic I'd look towards the gearbox rather than the engine.

Hey Damian. The car is a manual. The Check Engine Light never comes on. The car just wants to stall sometimes. The revs drop from about 1 to 8 when its in nuteral. Sometimes when I slow down at trafficlights, it just stalles?

I had a problem with the variocam solenoids on a couple of banks which caused my 996 to idle roughly and stall a number of times. This never threw an engine warning light but was diagnosed on the spot once plugged in at the indy.

I would say you throttle body may need cleaning.

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I had a somewhat similar problem to this recently on my 996 turbo, that I've just fixed. I noticed idle wasn't as even as normal (even though the Mezgers aren't exactly the smoothest idling cars), and when hot and at a standstill, the revs would drop off from idle and the engine would almost stall, before catching itself and briefly flaring the revs to compensate. It would do this repeatedly, almost you might say rhythmically I recently had the air filter changed as part of a service, and it was suggested that an air leak in the intake could cause such a problem. Went and checked the big jubilee clip on the intake hose nearest the MAF (the one that is loosened to remove the airbox - in the air path, it’s after the MAF) and it wasn't very tight. I tightened it up, took the car for a drive there to get it properly warm, and it's now idling fine again. If there is an air leak after the MAF, which is a key sensor for the engine management, then of course you are going to have issues! Note this is different from a boost leak as this is in the “low pressure” side of the inlet For anyone coming across such a problem in future.