I have a stock 302 Explorer motor. I bought it new from ford racing. It now has about 65,000 miles on it.
It backfires on the drivers side when cold but gets much better when the block comes up to temp. Even when warmed up it still sounds off on the drivers side.
3 of the plugs look fine. one is oily. (bad valve seal?)
Compresion on all four cylinders is 110 PSI
All 4 injectors read the proper resistance. ( I have not pulled them out to do any further testing)
I pulled the valve cover and to my untrained eye everything looks OK. Rockers, springs, push rods all apear to be OK. I ran it at idel with the cover off and all were getting
oil and doing there nice little dance.
So I'm thinking a sticky lifter? Can I do more testing for this, or is there some magik
oil additive that will free it up.
I run Casterol syntek blended
oil and oil presure seems good. 30 psi more or less which is where this engine has been since new.
any help would be great.