A little background,

This is a new odor (strong mildew I think) that started when I got it back from the dealership. They did the HG replacement along with new water pump, timing belt, idler pully, tenionser, radiator with hoses and new plug wires.

The smell is coming from the front right corner of the engine compartment, somewhere around the battery, radiator and PS pump. I dont see anything leaking and the smell is there when the engine is hot or cold. But seems stronger when the engine is hot. I have search and couldn't find much on this topic. Someone said maybe the heater core, but I dont know. Anyone else have any ideas?

 

so it's just in the engine compartment or is it in the cab? cause when i got mine back for a couple days it had an odour, what im assuming is exaust fumes and any fluid odours from the mechanics work attire when he drove my runner.

 

its coming from the engine compartment, but if the wind is right it overwhelms the cab at a stoplight. I thought the same as you but it has been 2 weeks back from the dealer and driven everyday.

It has to go back again cause the idle is all screwed up. I thought that after the ECU relearned it would be ok, but not.