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Andy, Truck Diagnostic Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 1649
Experience:  International and Isuzu trucks , International, Maxxforce, Cummins and Isuzu engines, Diagnostic and electrical troubleshooting specialist , Hvac and truck /trailer refrigeration troubleshooter
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I am working on 2004 kenworth t800 truck with cummins ism

Customer Question

hi i am working on 2004 kenworth t800 truck with cummins ism engine. ( vin# ***** and esn 35091571) truck have no power while driving down the road. no codes, no check engine lite. if i disconnect the egr valve truck runs fine. so i changed the egr
valve new. still same thing no power driving down the road and not much boost pressure. if i disconnect the egr valve truck runs fine, good boost pressure and power. no cac air leak , all battery connections are good and clean. all injectors are working good.
proform injector cutoff test. everything checks out good. what controls the egr valve? oh also it have new ecm as well.
Submitted: 2 years ago.
Category: Medium and Heavy Trucks
Customer: replied 2 years ago.
just waiting for an answer?
Customer: replied 2 years ago.
still waiting?
Customer: replied 2 years ago.
seems like experts are too busy? i am paying extra for urgent! if u guys can not answer in few minuts then don't charge me plz.
Expert:  Andy replied 2 years ago.
Hi there MY name is Andy ! Sorry about the delay ! I just got on and noticed that you were not looked after yet . This almost sounds like a wiring issue. Perhaps the valve is being kept open when plugged in . This would definitely give you low power because you would lose exhaust back pressure needed to run the turbo when it needs it the most .
Expert:  Andy replied 2 years ago.
I will look for a troubleshooter for this but in the meantime , I would check the wiring harness for possible rubout , damage to it . Maybe even do a pin to pin test to make sure they are wires crossing inside the loom
Expert:  Andy replied 2 years ago.
Let me know if you need a hand testing the harness with pin to pin checks . We could use skype audio to work on this .

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