Bo-Jangles
Registered User
1989 F-250 / 5Spd w 148k miles. When the rpms are 2k or above and I let completely off the accelerator pedal it is hard (stiff) when trying to get back on the throttle. There seems to be excessive resistance at the point of initial throttle input. This issue goes away when the rpms drop below 2k. Based off the maintenance notes of the previous owner the injection pump had been rebuilt at 125k but the truck sat for quite a while before i purchased it. Since owning I have run quite a bit of diesel kleen through it with every fillup as well as filled new fuel filter with straight diesel kleen to try and clean any gunk out that might have resulted from it sitting. Other than that the engine runs consistent through the rpm range, it's just the stiff pedal at higher rpms that seems odd. Any ideas what this could be? Time for a new injection pump? Thanks for any input.