Forrest Gump 9

Friend or my have a 1990 964 C4 that I'm looking to buy. The car is mint inside and out. One problem, upon start up it would smoke like crazy. From my research it probably needs top end rebuild. With that said, would you buy it? How much am I looking to spend to get it back to normal?

Car is black on black with 75k miles.

Spyerx

For the right price sure. Do a leak down and see if there is an issue with the top or bottom end.
Top end only? 8-15k give or take a few k. Big range. That said assuming its not been abused, regular oil changes, it would be rare for bottom end to have issues, top end may need a valve job.

rotorheadcase

My 1990 C4 will smoke on start up if it's been sitting for more than a few days. Had a full rebuild 30k ago so engine is relatively new. It's apparently not unusual for this to occur. Various fixes available including check valves installed in the oil line.

http://www.rothsport.com/Products/Engine/Oil-Inlet-Check-Valves/Oil-Inlet-Check-Valves.htm

newsboy

Get a PPI from a good independent, and base your decision and price on the results.

Porsche930

What color is the smoke? Did you check oil level? You might want to check the engine oil level at idle operating temperature using the oil tank dipstick to make sure it's not overfill; overfill oil will likely cause smoke from exhaust.

creaturecat

way too common on these cars, the overfill of the oil.
i would start there.