1997 4.2L about 60k miles

Check engine light came on. Symptom is slight pinging at moderate acceleration with no trailer. With trailer constant pinging. I read several posts suggesting throttle body cleaning and inspecting vacuum line to EGR valve. I have to drive my truck for 1000 miles hauling a car. I don't have time to drop it off at a repair shop.

What if I buy a high octane gas and if no pinging, start off the long drive?

 

high octane gas will improve power and mpg. not sure if it will stop the pinging or not. but definitely worth a try. speaking of the 4.2 engine you have they are not all that strong when it comes to towing. towing a heavy load as long as you are going i would use high octane gas to begin with

 

here is some info about that code:
https://www.autocodes.com/p0401_1997_ford_f150.html

 

Trip is done. Mid grade gas worked. Now I need to work on p0401. What junk yards are near Dallas?

 

Either google pull a parts or use car-part.com to find a part in junkyards across the country (can sort by closest to you first)