Engine/Transmission (1998.5 - 2002) low power no throttle response

[Mhannink]

ok so my truck is not right. sometimes(at random) it will act like a dead pedal wont accelerate hard. if im cruising and i accelerate the transmission might down shift and then shift back up and no power boost is 10 to 15psi and absoluetly no smoke.

 

[FourBarR]

You need to get a code reader or have the codes read by someone. There are a number of things that can cause this symptom. Fuel pressure from the lift pump,does the pump run when you bump the starter but not start the engine? Have you reset the apps ? Does it matter if the truck is hot or cold?If you get the codes 0122 or 0121 is apps trouble, may need to replace it (expensive) If you get code 0216 it is the vp-44 injection pump (expensive)Lack of boost can be loose clamps on the intercooler piping . Hope this gives you some information thats helpful. Good luck with it.

 

[WardJ]

As you are driving along and this happens, turn the key off and restart it immediately. Mine would start working for a while before the dead pedal occured again. It was the VP44, but I drove it for a month before I changed it out. It will be more difficult with your automatic transmission than it was with my 6-speed, but try it if you can and see if this is the problem. Apparently the pump loses its timing advance and what I tried 'reset' it temporarily. When you step on it you can hear the injectors pushing more fuel, but without the timing it accellerates very slowly or not at all. Sometimes just holding the pedal to the floor would restore it and it would take off and accellerate almost normally. Pushing in the clutch and pushing the pedal to the floor would work also.



YMMV

 

[Mhannink]

well i can hit 40 psi on a good day with the truck running right so its not loose boots. i tried the rolling shut down today and it didnt work. i dont know if there are any new codes since the check engine light has been on for a map sensor for a while. one buddie said it was the crank sensor wich i replaced a while back but i know aftermarket ones can go bad fast. lift pump runs fine and is suppling good pressure.



keep the ideas coming

 

[sslechta]

I had similar symtoms recently - on occassion the truck had a dead pedal feel, but in nuetral it would rev fine so it didn't seem to be the apps. No codes in the system. I thought the VP44 was going so had it replaced. One hour after the install the symtom came back again. Limped back to the shop and again no codes. We did find though with the plug-in code reader/diagnostic tool was showing 0 boost but my gauge showed at least 4 or 5 psi. Changed the boost sensor and all is well. We decided that since the bad sensor was reading 0 the ECM was defueling which makes sense. When this would happen the truck would barely limp along. It might be something you could check out or even replace fairly inexpensively and easily.



Good luck.