Engine/Transmission (1998.5 - 2002) CE & bucking & bad performance

[DSiemens]

On a long drive yesterday, about 300 miles into the drive my truck started to lose speed. Would only maintain about 70mph for about 5 mins. CE light came on, so some code has been set. Next the truck bucked a couple of times and speed increased to about 80mph. At this point I can tell performance is down. In climbing overpasses the truck will loose speed & some times buck. This is at WOT.



During all the events the Fuel pressure was never below 11psi. Boost ran on the low side about 6-8psi. , at 80 ran a little over 10.



From reading the forms, the truck does not seem to be in a true limp mode as I am able to generate more than 4psi boost. The only performance mod is a EZ box.



I changed the fuel filter about 50 miles before starting the long drive. I also installed the tap fix for the KDP at the same time of changing the fuel filter. The truck ran great up until the problems began.



Any ideas? The bucking makes me think I have some fuel supply issue, but could this be a map sensor or something else?

 

[silverram323]

When you say bucking is it like a chugg chugg (shaking) or is it like dead, no matter how much throttle except full throttle and it kicks out of OD. Mine has a dead spot at 50-60 no power and the boost will not go over 4 psi. The lft pump has been changed once and is in the dealer right now for another. Hope this helps

Kevin

p. s take a look at my post

https://www.turbodieselregister.com/forums/showthread.php?threadid=75862

 

[DSiemens]

Seems like it has better power when cold. The bucking was more of a power on , power off, power on. Today it bucked climbing a small Kansas hill in 4th about 40mph. The power completely fell off after it bucked and was in a more severe limp mode.



Does anyone know if the scanner that is usable at Advance auto will let you get the codes out of the truck? Do I need to go to a stealer to get the codes out? Mine is a 98. 5 so I the 3 key on deal does not work. :{



Thanks. At least it has not left me on the side of the road.



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Please refrain from the generic use of the word, "stealer" on the TDR website. Feel free, however, to post specific details about good - as well as bad - experiences with any dealership.



Robin

TDR Admin

 

[KWIKKURT]

What was your tach doing?