Hey guys, so recently I had to replace my valve covers on my G35 due to a VC leak that had gotten pretty bad (loss of power, Oil burning resulting in smoke from passenger side engine bay/from behind the front right wheel.) I took it to my mechanic who replaced both Valve covers and the gaskets, and all 6 spark plugs. The loss of power is gone, however it still smokes a bit when I park it after some casual driving. My mechanic said he cleaned up the engine bay for me and let it idle to burn out as much oil that was built up, but it still continues to smoke although it’s much less than before. Any ideas if there’s something else leaking? Or is it just still burning off residual oil.

EDIT: I noticed the loss of power isn’t as strong but still there, the car stumbles a bit at lower speeds. Arrows point to where I see smoke coming from. This is closer to the front right side. I was worried if this was a early BHG symptom, but inside oil cap looks fine. Oil in general looks clean, coolant didnt bubble at all under the radiator cap. The overflow tank was quite low on coolant but I expect it to be because the car was cold and also I have never topped it off.

 

It could still be residual oil. You can use simple green and lightly washing the engine bay to help remove any oil residue. Just don't soak the air filter or any electrical devices.

My valve covers currently weep a little oil. I was getting a similar experience, a few times when I parked the car I could see some oil vapor coming from the car. What was causing most of my leak was the O-rings on the cam sensors on both sides were cracking & brittle. I thought for certain it was the valve covers (and ordered them in advance). BUT, when I went to change the oil I was able to look up at the valve covers from underneath. Valve cover area was moist, but not soaked like I expected. Then I saw the oil was seeping down the heads from below them, at the cam sensors.

 

solid tip, thanks for the advice. I’m not sure if I’ll be able to get it done myself but I’m gonna ask my mechanic to check those O ring seals and also check the oil coolant ring seal because I hear those could be the culprit as well

 

Woahhh... Thats a lot of oil on the frame rail.
Check the power steering hoses and hard lines. They run on the passenger side from the reservoir down to the rack.

 

Did he spray down the engine while it was apart? When I did my valve covers back in October I cleaned everything while I had the engine apart, maf sensor, etc... everything. I also took some of that cleaner and just cleaned the engine all out as well... between the drips when topping off the engine due to the leak and oil changes not using a funnel to refill and the leak, there was a good amount of oil spill. Just took some of that maf cleaner since I had a couple cans and sprayed it all down. Nice and clean engine and smell and smoke were all gone. I had the same thing, occasional smoke on the passenger side prior to changing them. Pick up a can and spray that engine down and see if that makes a difference.