pinging underload

[bill53]

under load my 94 ranger 4.0 with 3.73 gears manual transmission pings, sounds like the timing is set to hight. I took it to two ford shops and they stated that all 4.0 do the pinging under load, and that the timing could not be set. One shop told me to go from 87 to 89 octane.
Question what do you think is causing the pinging?

 

[88ranger2.95sp]

honestly, maybe you should downshift. i had the same problem. maybe your timing chain (or belt, i am not sure which one) is stretching and affecting timing? i dunno, i am just throwing out ideas.

The change in fuel should work, no reason why it wouldn't.

 

[Donnie strickland]

under load my 94 ranger 4.0 with 3.73 gears manual transmission pings, sounds like the timing is set to hight. I took it to two ford shops and they stated that all 4.0 do the pinging under load, and that the timing could not be set.

Half right. The timing is indeed not adjustable, but their statement "they all do it" is garbage. Going to 89 octane would help, but first check your MAF sensor (do a search on this site). Mine was very dirty and caused this problem until I cleaned it.

 

[bill53]

Thank you I will check out the MAF sensor.