Engine/Transmission (1998.5 - 2002) Friend needs help!

[rono]

A friend of mine needs help and does not have a computer so he hasn't joined yet. His 2001, 3500, ETH,DEE, is a welding rig that grosses about 10k. He looses power going down the highway and speed drops down to about 50 with pedal on the floor. If he pulls over and stops then puts it in gear and starts going again and power is fine for a while. We changed the fuel filter and air filter. Lift pump runs when starter is bumped. No guages to check pressure. This is his work truck and makes a living with it pipeline welding. Any help would be appreciated.

Thanks,

Ron

 

[OL RATLR]

needs help

Rono! You need to get lift pump pressure tested.

Just hope it is lift pump and not injection pump.

Lift pump will still run but not puting out enough

pressure. Hope this helps.

Mine went out at 26000.

 

[georgej]

When the last time he changed the fuel filter??

 

[Pit Bull]

Just tell him to take it to the dealer and tell them he has low power pulling the load on his truck. That is what a bad lift pump causes and they will check the presure.

 

[BillGotthelf]

I agree with the group. Symptoms sound like the same I have been through 3 times all were lift pump.

 

[klenger]

It sounds like the ECM in his truck is running Windows 98. If it slows down and run poorly after running it for a while, you need to close all the windows, shut down the truck, wait 30 seconds, start the truck back up, and then open all the windows again. It will work fine for another few hours, and then you need repeat.

 

[LSMITH]

Originally posted by klenger

It sounds like the ECM in his truck is running Windows 98. If it slows down and run poorly after running it for a while, you need to close all the windows, shut down the truck, wait 30 seconds, start the truck back up, and then open all the windows again. It will work fine for another few hours, and then you need repeat.

LMAO, at least it is not Windows ME, that would leave him stranded anytime he needed the truck!!!!

 

[rashwor]

Fuel restriction, MAP Sensor, IAT Sensor

Most likely, it is fuel starvation: low lift pump pressure, clogged filter, clogged srainer in tank, or debris in fuel line somewhere.



If the MAP or IAT sensors are bad / dirty, they should set the check engine light. Either one with a problem will cause the ECM to reduce fuel, thus reduce engine speed.



When my MAP sensor went out, it was intermitant and the check engine light would come on, ECM reduced fuel, and the truck would do real good to run 50 MPH on flat ground. Up a hill, it was about 30 MPH in 3rd gear. When the CEL (Check Engine Light) went out, it would run like a champ.



My . 02.



Hope I helped.

 

[dpope]

Try checking the fuel vent cap on top of the fuel tank. It may have been left on at the factory.

 

[rono]

Thanks for all the replys. I was thinking the lift pump also even though we could hear it running. I also agree with the windows theory. I run a Mac at the office and it is super reliable so therefore I don't have to deal with the windows problems.



We'll get the pressure checked and hope that the IP has not been hurt.



Thanks again, Ron