my truck was running fine, let my daughter use it, then she said it was not running right. i went and got it. it misses at idle. and when i would drive it normal it would miss. but if i would punch it, it would hit on all six and run great, untill i let off the petal. i noticed a slight backfire 2 times while punching it just before it started hitting on all 6 again. check engine light is not on, and no codes.
i have put new plugs, wires, and coil pack, all motorcraft parts. and i checked for vacume leaks, by spraying wd 40 and also tryed using propane. ok guys any advise? i would love to hear any ideas
thank you jim

 

When was the last time you changed the fuel filter?

Put some fresh gas in along with a bottle of Techron.

 

i have had the truck for 2 years, and i have never changed the fuel filter. i will pick one up tomorrow, and change it. i will post if it fixes it or not, thanks, jim

 

How often should the filter be changed?

 

Every 30k.

 

well i changed the filter, and it runs better, but still has a miss. where do i find techron? and does it clean the injectors? thanks

 

Walmart and all parts stores have Techron - and yes, it *IS* an injector cleaner - the only one officially approved by Ford, as a matter of fact.

 

thanks again for your help, i found it at a speed shop today. i will fill up and add it to the tank, and put some miles on it. and see what happens.

 

well i have put techron in and filled up my truck. and it runs better at idle, and punching it, but still misses between the 2. any other things i should check? should i check the fuel pressure at the rail?

 

well took my truck to another guy. and i found out my truck needs a new fuel injector. i should get it back by sat.