went to put a quart of oil in today and there was yellow foamy crap on the bottom of the cap.anybody know what this is?

 

Don't forget about that handy search function:

https://www.rx7club.com/showthread.p...threadid=37361

 

Depends on your driving. Was the motor recently cold?

If you just drove a few miles for a few minutes, it could be water condensation just from surrounding moist air in the engine compartment. This is normal for all cars.

If you drove around for an hour on a hot day and saw this after stopping, you have problems. Then it is water leaking from the water jacket to the oil jacket somewhere. I think there is a test to see if the oil has antifreeze in it or the antifreeze has oil in it. I believe it is some type of litmus paper you can buy at an auto parts store.

Good Luck,
Tim

 

Please don't tell us you are using PENNZOIL!
That stuff leaves that nasty yellow residue all the time.
If there is ONE oil that I don't trust, it is PENNZOIL.