A few rubber gloves, rubber bands and some cheap mini cigars from our local gas station or convenience store.
Also get a good, bright LED flashlight to locate the escaping smoke. Look deep in the engine compartment and under the engine if needed. Do not forget the dipstick guide tube and the lower CCV oil return line. These areas may be hard to see from above in the engine compartment.
After looking for intake air leaks, remove the oil fill cap and allow the crankcase to fully fill up with smoke, then replace the oil fill cap. Check for cracks in the valve covers and leaks around the grommets, half moons and around the perimeter of the valve cover.
Common areas of leaks:
Upper and lower intake boots
Upper intake boot around F connector
DISA main O-ring and shaft area
Vacuum hoses under the rear of the intake
Fuel pressure vent hose that connects to the F connector on the upper intake boot and under the drivers floor board where it connects to the fuel pressure regulator
CCV and hoses, especially the lower oil return line
Dipstick and dipstick guide tube
Oil fill cap
Valve cover gaskets and cracked valve covers
SAP vacuum line to Kombi valve on front of engine, this will not leak smoke because of the control valve under the rear of the intake
Power brake booster sucking jet pump and hoses.
Note that the brake booster usually cannot be smoke tested because of the input vacuum check valve at the booster connection.
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