Engine Cut Out

[RWherley]

I was driving around 35mph when the truck started to buck it would drop to idle then come back up to where the throttle was real fast 3 or 4 times then it was fine, to running down the highway at 70mph when it dropped to idle and stayed there for 15 to 20 seconds then it came back up and ran fine. Both times it was running fine before and then after oil psi, turbo boost, and EGT's were all fine before and after. the fuel tank is around 1/2 full both times.

 

[JLEONARD]

Sounds like it could be gelled fuel. Also could be a lift pump going bad. Both have happened to me and sounds like similar symptoms.

 

[RWherley]

the lift pump is only about 2 mouths old and both times the temp was around 40, and I always run anti gel this time of year, the truck ran fine 2 weeks ago in -2 temps so I don't think the fuel gelled.

 

[mwilson]

I'd still change the fuel filter first. Sometimes they just give up.

Mike.

 

[JLEONARD]

the lift pump is only about 2 mouths old and both times the temp was around 40, and I always run anti gel this time of year, the truck ran fine 2 weeks ago in -2 temps so I don't think the fuel gelled.

At 40 then it is NOT gelling. My new lift pump was about 1 year old when it gave out....at least that was after the third time I got towed and finally narrowed it down to the pump. It had been "going" for several months prior. The fuel ate up the rubber inside.

 

[RWherley]

I'll change the filter and add a fuel pressure gauge and watch to check the pump.

 

[DVolk]

This might sound real stupid but check to make shure your injector pump bolts are tight !!! mine did the same thing on my 92
it had a bolt back out and fall off , i dont know if someone tried to steal it or what but it loosened up and bucked jumped etc .....