Engine/Transmission (1998.5 - 2002) Lost boost under load

[DWest]

Title should say no boost as it drops to zero. My truck has done this occasionally but now I can do it all the time. Start down the road under normal throttle and all is fine, put a little extra fuel or a load behin and the boost falls off completely. Let off the fuel and it goes back up. When this happens it sounds like a slipping belt on the turbo side of the motor. Could it be the wastegate actuator has sprung a leak or could it be the exhaust brake? Sure sounds like vacume to me. DW

 

[Cummins724]

Have you checked your intercooler boots? The boots can be popping out from under the clamps.

 

[DWest]

Boots yes

All boots are tight, only problem is hard throttle, can run to 30 lbs if I feather the throttle. This is a Dodgezilla and I do run the smarty so its fast spooling.

 

[Cummins724]

Crimp the hose on the wastegate or adjust your boost elbow shut & take it for a ride. See if the noise is still there. Then do a boost leak test to find the problem.

 

[DWest]

Not the actuator

Put the original actuator on no change, clamped hose to wastegate no change. Am going to plug air intake and try to pressure test the intake system, more to come.

 

[MCummings]

Possibly is the conpressor wheel rubbing the housing?



Remove the intake and check for play. Shouldn't have more than . 020" in any direction, but . 020 is fine.



Merrick

 

[DWest]

Pressure test

Clamped everything off and tested, no leaks. Put a piece of rubber over the set screw on the boost elbow and clamped with vise grips and it ran fine. Set screw is firmly in place with rust. DW

 

[WestTN]

It sounds like the engine is running out of fuel. I don't see a fuel pressure gauge in your signature. De-fueling will always cause loss of boost.

 

[DWest]

clogged air filter

Air filter was not flowing enough air and was collapsing. End of story