Oil Leak

[19Glendale]

In my '98 Avalon I've got an oil leak which I can visibly see the oil towards the "back" of the engine block ie where it is closest to the windshield. When the car has been sitting for a while (off) and had ample time to leak some oil (eg overnight) and then it's driven for a short while and then turned off, smoke from the burned oil (I assume on the outside of the engine block and pipes that the oil encounters) is visible when the hood is raised and can be smelled if just stopped at a traffic light.

My dad -who I inherited the car from, suggests we use engine cleaner to spray the engine block with and clean all the excess leaked oil to identify the location of the leak.

Are there any likely locations or diagnoses for this leak? I have checked the oil level regularly and have driven 2000+ miles with this symptom and have not noticed any measurable difference in oil level.

[pmesfun]

It is very likely the the rear valve cover gasket is leaking, common on the 1mz-fe. First check to see if the leak looks like it is coming from the top and running down the back of the engine this will indicate the gasket is leaking. If not, get some engine degreaser and brake cleaner and clean the engine thoroughly. Once you do that watch for new leaks to develop and that will determine where the leak is coming from.

[robcam13]

pmesfun is right i would bet its a valve cover gasket. very very common problem

[Chunkywolf]

I'm having the same problem on the front of the engine, Haven't spent the time to figure it out yet though.

[ImDisaster]

In my case it was the transmission pan gasket. Your dad's idea, of cleaning it well, and then looking for the source is a good one. Otherwise you've got dirt and oil everywhere and it is impossible to diagnose.