91 4.0 ohv, 180,000 mi, maf sensor went bad, put one on from a 5.0 crown vic, the engine pinged before the new maf, it does it a bit more now more so when it gets hot, I read somewhere that the maf sensor controls timing, also just read that if the timing chain is loose or the tensioner is bad it will mess with the timing, Other than the normal ticks and noises it runs good.

 

It could just be carbon deposits in the combustion chamber.
Get a can of Seafoam and run some through the intake.

 

could have low compression causing it to ping under a load.

 

Thanks, it has power and doesnt burn oil so compression good, I will try some seafoam.