I recently purchased a 1990 f150 with the 5.0. The engine pings under load and I've tried several things to fix it, I've used high test gasoline and adjusted the timing by turning the distributor both which seemed only to help a little bit. I'm thinking about replacing the timing chain in hope that it'll solve the problem, I also want to check and see if the knock sensor is broke or not but I do not know where to find it. Any suggestions or information would be greatly appreciated.

 

 

The sensor alone might not be enough to correct the problem, you can test it running the KOER WOT test, might save you digging for a working sensor unnecessarily.

Have you run the self test checking for stored codes? if not it would be a good place to start, a lean condition due to secondary air or dirty injectors would cause spark knock....among other things, it's a good place to start if you have not done so yet.

 

Good luck trying to find a replacement knock sensor. Even the aftermarket stopped making them several years ago. Almost made of unobtainium.....

I agree with Dan, run some tests before going down the bunny hole of the knock sensor replacement.

 

What is the condition of the air injection system? A leak in the plumbing associated with this system will can an excessively lean condition, the usual cause is a broken check valve or rusted metal line at the back of the motor, most everything else in the system is silicone rubber.