Maybe a head gasket?
If there is exhaust popping on the BMW 318 series, then take your vehicle to the mechanic.
You should take your vehicle to the mechanic if it is letting power and exhaust popping.
Bad ignition coil
Possible causes of popping/grinding noises when turning:Wheel bearingsCV joint / axleBrakesSee "Related Questions" below for more
no popping popcorn is
When was the last time you changed your O2 sensors? They are supposed to be changed about 60,000 miles. Could be responsible for rough idle and popping in the exhaust. Otherwise it is likely a vacuum hose that is leaking.
The popping from the exhaust and the lack of power sounds like there is something in the timing. Most likely the timing chain is worn and needs replacing.
Many things could contribute to popping noises in the exhaust when warm. The most common issue is running a car rich with fuel. With more fuel burning more back pressure is created in the exhaust and the popping noises is back pressure attempting to escape the tail pipe. A few things you can do...1.check your ignition timing 2. check idle to factory specs 3.check you fuel injectors 4. check overall engine compression
If your talking about it doing that after you have turned off the engine then yes. That's just the hot exhaust pipes and catalytic converter contracting as they cool.
Answer Not running on all cylinders, bad valve, plugged catalytic converter Mixed up firing order.
Trottle sensor...
may be the computer im having same problem second cylender is not firing and gas pooring into it ive done head gaskets and all only thing left is computer