93 Z34 with issues

[SiNNERZ34]

OK...here's my symptoms.

 

1) Insane smoke clouds at startup. You'd think something was on fire. Yes, it's oil smoke.

2) Oil leak. It's eaten about 2 and a half quarts in a week.

3) Smooth idle, but every now and then it diesels at idle...pulses +/- 300RPM from normal idle (950 on my tach)

4) No smoke once vehicle is warm, although romping the gas will sometimes release a little puff from the tailpipes.

5) No loss of power. Pulls strong through full rev range, holds constant speed well.

 

Every gasket short of the head gaskets and oil pump drive seal was replaced (yea, call me lazy). The oil pump drive seal is not leaking, however. The only external oil leak is a small drip from the pan...dunno if the gasket is maybe bunched up or the pan is slightly warped. The biggest puddle I've seen under it is maybe the size of a silver dollar after sitting over night. The thing that is throwing me off is that it runs and drives perfectly normal.

 

It also sucks because I have a small exhaust leak...somebody bent the flange that goes over the donut gasket...even exhaust sealer doesn't seal it 100%. When I start it up, smoke comes out the hood vents (actually looks kinda cool lol). This motor came from a junkyard, out of a 93 Z34. It had about 80,000 miles on it. This problem cropped up about 3 days after the motor swap was complete -- the first time I noticed it was right after changing the upper/lower intake gaskets and fuel injector o-rings (old ones were leaking).

 

Could anything other than valve stem seals or a head gasket cause this? Bad head (warped/cracked) maybe? I don't think it would be rings since oil is getting in the cylinder mostly while the car is off. I have another top half of an LQ1 on my dining room table if it's a top-end problem...

[birdman]

well the smoke on startup id almost bet is your valve guides, once the engines gets warm they expand and stop leaking. the other problems could be caused by timing possibily. id check your belt.