Engine/Transmission (1998.5 - 2002) Bucking

[GBBrown]

Out of ideas...help. While running at a steady speed (55~60) truck will start a slight bucking or missing. While Speeding up or slowing down it goes away. Truck has plenty of power and idles fine. I've replaced the apps with a timbo and did the reset, pulled and cleaned the IAT, replaced BHAF, cleaned and tightened battery to block ground. Anybody have any ideas?

 

[JR]

Check for codes yet? If your cruise is vacuum controlled, try setting the cruise next time it starts acting up. If it goes away, good chance you still have an issue with either your APPS or something in the wiring to it. A VP on its way out could cause fuel delivery issues and a bucking. Any codes you have stored may help narrow it down.

 

[NIsaacs]

Sounds like your EZ is going south, unhook it and try again.

Nick

 

[RonaldLarson]

I vote for EZ failing. I had identical issues with mine. What is your fuel pressure?

 

[mfurrh55]

Same here with the EZ,turned out to be wiring to injection pump, cleaned connections and fixed problem

 

[GBBrown]

No codes. Have steady 15 lbs fuel pressure to VP. Will disconnect EZ and try that.
Thanks guys.

 

[GBBrown]

Well I replaced IAT sensor and didn't help. Disconnected EZ and no help. Finally I did the APPS reset again and problem appears to have been cured.