Q: car running very rough, making oil 1990 Nissan/Datsun 300ZX

asked by on December 05, 2016

The car was running great. The next morning when it was started it was smoking very badly and barely ran. I checked the oil, it is over full and smells like gas.

My car has 70000 miles.
My car has a manual transmission.

Hello - I suspect your cold start system has gone "full on" or you have leaking injectors. Without question your fuel system is pumping way too much fuel into the intake, leaking past the piston rings, and entering the crankcase. I would recommend a engine fuel system inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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