When i get up to about 72 mph or so and hold it there for a while (5 minutes plus), my truck decides to drop all excelleration as if i let off the pedal... It doesnt matter how hard i push, i loose the throttle responce... In about 20 seconds, i regain control of the trottle and the truck has complete power again... It did this five times within about 50 miles one day on the interstate...

I've used three different settings on my tuner, took cruise off all together, and I still have the problem... The tuner records show normal operation and all my guages look normal during this...

It doesn't act like a fuel filter, and being the current filter is new, i don't see it being that... And i don't have to pull over and turn the key off, etc... I'm stumped here... ANybody have problems like this??? I'm thinking throttle position sensor, but wanted some other input before assuming anything...

 

I've had the same problem when I pull real heavy loads. It's just over boosting it doesn't do any damage but if you have a chip it should over ride it and it shouldn't happen

 

I didn't think you could overboost a STOCK LB7... mine does it with truck only, no trailer or load... makes me wanna light it on fire and walk away haha, can't do that tho...

 

i hear ya idk man i would check the fuel filter because my buddie has a lb7 with a new filter and the same thing was happening and he put a new one one and it was fine. i think trucks just have minds of there own

 

Makes me think maybe a sensor somewhere, but there must be 1000 sensors on the power train... Maybe i'll try another new filter and see what happens, allthough it did the same thing with the old filter...

 

Even though its a cummins, my dad had the same problem. We got a new fuel filter and fixed the problem.

 

Yeah, i did the fuel filter about 2000 miles ago and it did it before that too... I have two thoughts in mind - over boosting or throttle position sensor...

I think GM has made the LB7's to not overboost on stock trucks tho... And the throttle sensor seems like it would do it at any speed... It makes me crazy cause i am totally lost with it...

 

PM sent

 

i had the same problem when i had a programmer, the truck never threw a code but it would all of a sudden die down and have no throttle response untill the truck got below 65mph.

it turned out that my truck had an over boost code issue.

 

That's exactly what's happening... I have to get below 65 or so before i get throttle again... Is there a fix for this???

---AutoMerged DoublePost---

I'm gonna put the programmer back to stock settings and see if it does it still... Then go from there i guess...