2nd gen oil leak

2009 Tacoma, 2.7 4 cylinder engine, 188,000 miles. Slight oil leak that burns on exhaust system. No leak on the ground. I replaced the valve cover gaskets and can still smell oil burning on the exhaust system. No visible leak. Any ideas where the leak could be?
Thanks Scott

 

Its either residual, or you have a leak. Either find the leak, or clean it up.

 

Have you been able to look from below and find any oil or stains on the exhaust pipes?

I'd recommend spraying down your exhaust with brake clean and insure the engine is clean.....then start the truck and look for a leak.

Forgot to mention make sure the truck is good and cold when you spray the brake clean.... otherwise that might not go well

 

I would not rely on "smell" to diagnose an oil leak.
I would refer to spots on the ground , smoke under the hood or low on the dipstick.
......easier to detect smoke in the dark in the rays of a flashlight beam
Burning plastic can smell like oil, I have had plastic bags blowing around on the road get stuck to the exhaust