Looking for some advice on how to diagnose this problem. I am cruising along at 70 mph/ 2200 rpm and I go to accelerate and the truck does not respond as I depress the accelerator - the truck does not decelerate but just maintains its speed. The only way to get it to break out of this dead spot is to coast down to a slower speed so that I can shift it into 5th gear; this seems to free up whatever it is that is stuck since the rpms change and I can once again accelerate now in 5th gear and shift once again back into 6th gear and cruise away. This does not happen all the time - jsut about every third day that I use the truck. Any suggestions about what to look for would be gretly appreciated. Thanks
fredster

 

do you have an after market lift pump

 

I do not believe so - just the stock pump attached to the engine. When I originally purchased the vehicle(this january) i read about the fuel pressure problems on line and the subsequent failures of the vp44 high pressure injection pumps - so bought a fuel pressure tester - screwed that onto the schraeder valve port and as i remember had about 6 lbs of pressure at 70 mph- i bought an in dash fuel pressure gauge from genos garage but have not yet installed . As astop gap measure I been running B20 fuel figuring the higher lubricity of the biodiesel componenet would keep the vp44 more lubricated so as to prevent failure - keeping my fingers crossed.
Fred

 

You need to install that guage now Fred. And check codes.

 

I agree with Dr. Evil.

 

Could be the APPS messing up also!! If you have a buddy with a scanner take him for a ride and have him read the throttle % and see if it is moving with your foot or just staying the same when your pumping the throttle.

 

Could be, but he doesn't mention it happening in all gears at the RPM. The fact that it is at 70 mph and that rpm leads me to think fuel.

Fredster....Does it do the same thing in any gear at 2200 RPM?

 

i would lean towards the APPS to, if it was fuel i would think it would start missing and sputtering...but could be both you need to get that fuel pressure guage hooked up asap like said earlier

 

A good OBD2 scanner will tell you the % of throttle on it.At 72 mph it doesnt move in % up or down there is a problem.Do you take it up to 2200 rpm in every gear? APPS have been **** to dead spots in the rpm range that is driven regularly, and not show a code, just from experience here.

 

No, just seems to be that 6th gear