Diagnostic help needed! Hot film MAF and low oxygen adaptation.

[Danimal]

Quick update. I decided to start my pulling and cleaning the throttle body. That way there would be more room to look around for anything obviously wrong.

The throttle body is dirty (64K and probably never cleaned), but pretty clean from behind the valve and through the intake manifold. There is some oil, but I think it is acceptable. The PO said the AOS was replaced at some point. Please let me know if this amount of oil looks troubling or not.

There was also a strong gas smell from inside the intake. You could immediately smell it after removing the throttle body.

That said, there is damp residue all over the lower pivot for the resonance tube valve. I've read this could be power steering overflow and there is a small old gooey puddle of it in one of the crevices on the block. Do you think this valve could be my vacuum leak? Or this is just old power steering fluid?

[Danimal]

Pictures

[Danimal]

more pictures

[Gilles]

Originally Posted by Danimal

Or this is just old power steering fluid?

Have you taste it? (seriously..) as oil and hydraulic fluid taste completely different.. you don't need to drink it, just the tip of your finger will give you an accurate taste..

[Danimal]

I dabbed a piece of paper towel in it and smelled it....but it didn't smell like anything....iI guess I should have tasted it!

Originally Posted by Gilles

Have you taste it? (seriously..) as oil and hydraulic fluid taste completely different.. you don't need to drink it, just the tip of your finger will give you an accurate taste..

[Danimal]

Here's a shot of the resonance flap hinge.

[Danimal]

The check valve going into the resonance tube boot is oily on the boot side. The PCV valve is also very wet/oily.

To replace to replace the check valve, is it just press fit?

[Danimal]

Here are pictures of the PCV and check valve.