good morning and i just traded a well sorted 78 f100 swb 2wd for a 1988 f150 swb 4wd. its has issues and i need some advice please. 1. it spark knocks extremely bad at part throttle.........i'm thinking egr. it hunts idle.... thinking tps. the third need is the fuel gauge the needle floats to both full and empty regardless of the amount of fuel. any help would be greatly appreciated. thanks teschwab

 

pull codes, www.fordfuelinjection.com has instructions. the float & sender are probably worn out.

 

Check it with a timing light and see if it is at 10* BTDC with the SPOUT out. If it is and you have good gas in it and it is not hot then I would think that it is not spark knock, it is piston slap.

 

prior to pulling the codes i started to check timing. pulled the sprout connector and loosened the distributor hold down. then as i laid my hand on the distributor to make a slight adjustment. the ole' girl shut down and will not fire up. engine cranks over fine just no fire in the holes. so i pulled the codes and it revealed code 14 pip circuit failure and 84 egr vac solenoid circuit failure and 21 ect, 33 egr valve opening not detected. my original post pertained to spark knock. the pip code explains the no fire deal, but could the pip problem begin with module. any idea's thanks tim

 

Did you somehow lose the ground connection on the small black wire with a green stripe at the Neg. Post of the Battery?

 

i suppose thats possible, this truck has had both cables replaced with the clamp on style. i will replace those very soon. i had not touch the battery prior to the shut down.