How much will it be to replace the head gasket at any common mechanic shop?
on 2001 BMW 330i

the car turns off by it sefl after a long time in drive, the accelerator also goes up by itself when I am at a stop, so ist really the gasket?

Asked by for the 2001 BMW 330i
agree w #1 and #2 get proper diag. the head gasket job will be expensive. appox 2000.00 to 3000.00 so a diag fee is cheap
2 more answers , 1 more comment
sounds like you need to get a proper diagnosis.First try to retrieve the trouble codes,if any that are set.does it overheat? are you low on coolant? the symptom you described sounds kinda like a vacuum leak.
I already did the diagnostics and one shop said it was the gasket
This needs alot of diagnositics. The problem could be a lean condition to a idle air solenoid,head gasket problems has with it other conditions.
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