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Jeremy, Certified Truck/Bus Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 3380
Experience:  ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, EPA 608/609 HVAC Certified, Steering/Suspension and ABS/Brakes Technician
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2005 Chevrolet C-5500 Duramax 6.6 Diesel engine, Codes Road

Customer Question

2005 Chevrolet C-5500 Duramax 6.6 Diesel engine
JA: We'll do all we can to help. Tell me a bit more about what's going on so the Heavy Truck Mechanic can help you best.
Customer: Codes Road Speed PID 84-FF1 3 , Percent Accelerator pedel position PID 91,FM1 3 and Exhaust Gas Re-circulation EGR valve SID 146,FM1 7
JA: Is there anything else important you think the Heavy Truck Mechanic should know?
Customer: Heavy black spoke and no power
Submitted: 1 year ago.
Category: Medium and Heavy Trucks
Expert:  Jeremy replied 1 year ago.

My name is ***** ***** I will assist you with your question today.

I'm an independent contractor and I don't get paid until a rating has been made.

We can go back and forth as needed to help resolve the issue you are having. Follow ups are free after ratings, so rate in confidence!

Check the VSS sensor for the road speed code. It is acting up. The high voltage code from this can be a failed sensor or a short in the harenss. I would try the sensor first since these trucks are bad on them followed by the pigtail. If the code remains, then check the back of the cluster and the ECM for that signal wire is bad with overheating on these and melting at one or the other plug.

The accelerator pedal sensor needs to be changed. It isn't reading the position or there is a dead spot in it. The FMI 3 is voltage above normal. I usually replace the sensor for the pedal and this code clears itself.

The EGR is just that, a bad EGR valve. the FMI 7 mechanical failure means it has failed. It will need to be changed.


You want a 5 star service and I want to provide a 5 star service. Please consider that I don't know your skill level as well as I can't see, touch, smell, hear the vehicle/machine in question. Please provide as much detail as possible and I will provide as much back.

Once an answer is provided, you should see a rating screen. Please rate my personal service to you. The ratings are my personal feedback, they are not the site feedback.

Thank you for allowing me to assist you through Just Answer!


Expert:  Jeremy replied 1 year ago.

I see you viewed this and this is still showing as an open question due to no positive (3 stars or more) rating.

Were you not pleased with my service to you or is there a rating issue? Please let me know if you still need assistance with this, if there is a rating issue, and/or you need more time to respond.

I like to make sure all my customers are satisfied since you did pay a deposit for me to assist you, whether I’m paid by a positive rating feedback or not.

We can continue where we left off or start over if needed. Also, if you need diagrams, instructions, etc please don’t hesitate to ask.