I have a 98 F-150 with a 4.2L V6 and Manual Transmission. The truck seems to hesitate everytime I push the gas pedal to the floor. If I slowly accelerate it seems OK, but it jumps whenever I "Floor it" I already replaced the fuel and air filters and no joy. Any help would be appreciated.
Chip

 

Try a K&N filter, or filter charger, and a fuel injecter cleaner (like STP)...should boost your power a lot - it works for my truck when it gets sluggish.....

 

How many miles are on the motor?

"Stuck with a m*par, Settle for a ch*vy, Happy with a Ford!!!!"

 

it has 40,000 miles on it.

 

It's a good idea to periodically run some spray fuel injection cleaner thru the throttle body. Take the hose off it from the air cleaner and spray it in directly. Also sometimes the air bypass valve on the side of the throttle body gets carboned up. the valve gets sticky inside and you need to remove it and wash it out with injector cleaner.

 

A cautionary note before spraying the throttle body of your .F-150: don't. I also have a '98 4.2 and was planning to do likewise as part of a routine filter change. Then I noticed a factory warning on the throttle body advising against spraying carb cleaner etc. on the parts as they are specially coated from the factory. Check it out for yourself. Andy