1987 ranger v6 2.9 all of a sudden truck started to ping it, belongs to my son. he reasintaly changed o,2 sensor and ign module. using same gas station same type of gas.changed out temp sensor also no diff. any ideas? thanks ahead of time. standard trans.

 

1st thing I might check would be ignition timing. Unplug the SPOUT connector and make sure base timing is at/near 10 BTDC. I guess I'm thinking that, maybe in the process of changing ICM, he accidentally advanced the timing.

 

thanks mrshoryt i,m also thinking maybe a bad knock sensor? friskyjake

 

the pinging problem changed out a new knock sensor drove truck 40 plus miles no more ping. drove it hard toburn up the junk in the cat &muffler. got home change the oil &filter drove again & it pinged the same as before. timing is 10 btdc @idle. any more ideas? thanks guys. friskyjake

 

pinging got it straitend out. with 1/2 tank of 87 octane we added to the other 1/2 94 octane , whopee no more pinging.sometimes we don,t see the simple things. we overlooked this. sorry for making a small thing very big friskyjake