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Daniel Wilson
Daniel Wilson,
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Experience:  Owner at DJ Wilson
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I have a 2004 Newmar diesel pusher with a 300hp cummins

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I have a 2004 Newmar diesel pusher with a 300hp cummins turbo diesel
JA: Sometimes things that you think will be really complicated end up being easy to fix. The Heavy Equipment Mechanic I'm going to connect you with knows all the tricks and shortcuts.
Customer: twice in the last thirty days i've had a considerable drop in power and a series of check engine light flashes between two and four hours into my trip. feels like the engine is lugging....lots of black smoke i have limped home both times i took it in after the first time but no codes would show up when it was scanned. any suggestions? fuel pump?
JA: Anything else you want the equipment mechanic to know before I connect you?
Customer: that should do it thanks

Hi my name is***** will be glad to try to help. If the engine light is flashing it means there are fault codes logged in the ECM. Scan or pull the fault codes and let me know what codes you have logged. This will point us in the right direction for testing and troubleshooting.

Customer: replied 4 months ago.
By flashing i mean that the light will come on as I'm climbing. The power will steadily diminish until I crest the grade. Once heading downhill the light goes out until the next climb. All gauges register normal (the engine temp will occasionally rise to the 2/3 mark) , fluids are all on the mark.
When this first happened I took it to a highly respected diesel shop locally. They put the scanner on it but got no codes. They then drove it and of course everything acted normal!
I am very much into preventative maintenance and am somewhat befuddled that there were no codes. The coach only has 62k miles and has never given me a minute's truoble until the last month. Is it a given that the ECM will store the codes once the light comes on? Maybe I need to find a different shop?!
Customer: replied 4 months ago.
Two weeks ago I drove 360 miles in 6.5 hours without a moment's trouble! Then on the return trip all was well until I got 90 miles from home.
Customer: replied 4 months ago.
I do not have a scan tool so I am at your mercy!

Thanks for the update. i help on here in between jobs as time allows but I will always respond back on my next available login. If you can get me the complete engine model from the ID tag that would be great. There is a way to pull flash codes by flashing the check engine light and counting the flashes.

Fault Codes
Fault code information can be flashed out with the operator interface lamps, read directly from the RoadRelay in-cab display or downloaded using an authorized Cummins' software tool such as INSITE.

You must use the diagnostic switch installed in the vehicle cab to flash out fault codes with the operator fault lamps. To check for active engine fault codes and maintenance indicator codes, turn the keyswitch to the OFF position and move the diagnostic switch to the ON position. Now turn the keyswitch to the ON position. If no active fault codes are recorded, both the warning and stop lamps will illuminate and remain on. If active faults are recorded, both the warning and stop lamps will illuminate momentarily and then begin to flash the codes of the recorded faults.

The fault code will flash in the following sequence:

  • A yellow warning lamp will flash

  • There will be a short 1 - 2 second pause

  • The fault code will flash on the red stop lamp

  • There will be a short 1 - 2 second pause between each number

When the number has finished flashing in red, a yellow warning lamp will appear again. The fault code will repeat the sequence.

Each fault code will flash twice before advancing to the next code.

Try this and let me know if you can get any codes.

Customer: replied 4 months ago.
Thank you. I now need to get my act together! I will get back to you as soon as I can.

Sounds good. Let me know

Customer: replied 4 months ago.
Dan I made an appointment at the Freightliner Dealer for tomorrow. If they can't pull the codes, there is an exclusive Cummins dealer a couple miles from there. I will visit them after I drop the coach off in the am in case the Freightliner people come up empty. Thanks for your help.

Thanks for the follow up. Keep me posted and its a pleasure to help.

Customer: replied 4 months ago.
I have a friend that's been a Cummins engineer for 37 years. Finally got hold of him this am.
He says Cummins sells what they call an "in line mini" that plugs in to the nine pin round
diagnostic plug. It sells for approx $150, is available only at a Cummins Dealer and is monitored
thru a phone app! I will be purchasing one tomorrow! Seems like a small price to pay for an
instant answer!
Thanks again for the help. I will let you know how it turns out!

Pleasure to help

Customer: replied 4 months ago.
I have a fuel pressure issue! The new shop was able to pull the codes.
Hopefully all will be well in the next few days!
Let you know how it turns out.

Thanks for the update. If you post the codes I can help with information on them if you need more help. Keep me posted.

Customer: replied 4 months ago.
I'll call and get them
Customer: replied 4 months ago.
Code 2215 "fuel rail pressure low" is what they are saying

Click this link


Customer: replied 4 months ago.
They're saying there's algae in the tank.
New filters will be in tomorrow.
Customer: replied 4 months ago.
They are putting an additive to handle the algae in also!

thanks for the update. This can be confirmed by running from a separate fuel container to bypass the existing t see if the fault is corrected. As well as a fuel test of course.

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