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Daniel Wilson
Daniel Wilson,
Category: Medium and Heavy Trucks
Satisfied Customers: 5158
Experience:  Owner at DJ Wilson
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I have Paccar mx-13 Engine with 485 horsepower. Around halfway

Customer Question

I have Paccar mx-13 Engine with 485 horsepower. Around halfway into a 400 mile turn, my check engine light came on and stayed on for about 20 miles. At that time I shut the engine off and the light did not come back on when I restarted it. The truck performed normal, no skip nothing, just a light had come on. Later that day, the shop put the computer on the truck and determined that it needed an EGR valve and a nox sensor. The EGR valve and sensor were replaced and, after that work, the truck has had a miss or skip like a low fuel flow issue. I've had it in the shop now 4 times and several things have been replaced including a wiring harness a clutch, the ECM on the transmission among those. I also had an overhead run on the truck. None of these repairs stopped the truck from having the miss and skip and it's going back in the shop this next week for the same problem. Any ideas about what might be causing my problem?
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  Daniel Wilson replied 1 year ago.
Hi Frank, My name is***** will be glad to try to help. Install a clear hose on the suction between tha tank and pump to monitor for air bubbles and monitor your fuel pressure for a fluctuation. Check for restrictions and leaks between the tank and pump as well. Is it throwing any codes when this misfire happens? If the fuel supply pressure checks out constant and no restrictions or air in the system then you could have an injector that is acting up. Have an injector test done and also check for a cold cylinder when the problem exists with a digital temp reader. Let me know
Customer: replied 1 year ago.
No codes. No check engine lights. Nothing. The shop says, if not fixed, Monday morning, then dyno test Monday afternoon. I really so not know what the dyno will involve.
Expert:  Daniel Wilson replied 1 year ago.
I agree at this point. the dyno will help monitor all parameters in live data through all speed and torque curves and will likely help isolate this problem
Expert:  Daniel Wilson replied 1 year ago.
Hi Frank, did you get this resolved?

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