92f150soslow

Hey guys and girls, i am new to the forum and in need of some help. For a while now i have had trouble with my 1992 f-150 with the 5.0, it ran ruff at idle but other than that it drove fine except for spark knock upon acceleration, so i changed the cap and rotor, wires were good, changed plugs. have checked distributor and ignition system all is good,fuel pressure is good, fpr is good,Ect good, Air temp sensor is good, but still the same problem. Then i found a couple of vacuum lines that were broke and so i fix and replaced a few of them. now the truck is running real rich, and back firing bad but it drives good. any ideas.

other things that have been replaced on this truck
-IAC
-TPS
-O2
-Map
-speedo sensor

Sorry if this is long but i want to have everything up here that i can think of that i have done,

Chris_1

iTrader: (1)

Did you set the TPS to .9 volts at closed throttle when you installed it ?
Have you checked the base timing (10 to 12 degrees BTDC w/ spout out) ?

92f150soslow

hey Chris_1 i have checked all these thing at my tech school and every thing was fine, the tps is new but i did check just because i don't trust any sensor right out the box and i did a timing check a week ago and it was dead on 10,also checked for slack in the timing chain. the rich problem happened after i fixed the vacuum leak, and i am out of school till January, so can't fix it there right now

92f150soslow

well i reset the computer and now trucks nearly running like a champ, but i did some other checking and found that my egr valve is not working, with vacuum applied it not making any difference in how the motor runs but other than that the truck has been fine, no more missing or ruff idle, and is not running rich no more, i think the computer just had to relearn air fuel mixture after the vacuum leaks were fixed, and it must have been that way for a long time because i could not find the parts of lines that had broke off so i am good to go from here