I need the forums help here with my 2005 2500 5.9 auto

I have owned it 8 years and it is about to roll 122000 miles. No tuner of any kind. I have ran the Baldwin 7977 filters changed twice a year in the spring and fall. Truck see's limited driving on weekends and some trips as I have a commuter car for the week.

Truck has had a very slight stumble on start up cold. Didn't think much of it. Truck always starts in hot or cold with no issues winter or summer. I got the valves adjusted this week. Truck ran great for a day. I realized I was going on 2 and 1/2 months on the same tank of diesel. I drove the truck on a 40 mile round trip a few days ago. Ran great. As I was leaving I fired up the truck and the idle acted weird. Raised rpms and back to normal. Did it a few times with somewhat of a surge then stopped acting up and I drive on the highway home with no troubles. Tank was about empty so I filled it up and put power service in thinking maybe I just had some bad diesel starting from being so long between tanks. Also changed the fuel filter. Truck still had a spell on idle every once in a while. Stopped back by the diesel shop and the mechanic talked with me and thought maybe my injectors were starting to wear. Gave me some ATF to put in the tank and said I was ok to go on my trip. My thought was it ran fine for a day after the valves were ran so maybe it was a fuel issue. I ran on my highway trip almost 600miles round trip and it ran fine the whole way getting 19mpg mostly on the interstates running 70-75mph. I have been back for 2 days and its been fine. Perfect idle and no issues. I was getting low on the tank again so filled it up and now have the same surge and funky idle again. You really cant see the RPM's change much. Looking at the reader it fluctuates a little. Rail pressure was what concerns me. It sits at 6800-7000 at idle and then when it has it surge it goes to 8400 all the way down to as low a 5400 and all points in between. Then truck idles fine and it sits at 6800-7000psi.

I don't think its bad fuel from the station. I know the guys who run this place and a lot of semi trucks go thru there as well as their fuel delivery trucks. They make sure they have good fuel. Batteries are 7-8 years old. I did clean the terminals. There is no smoke on idle. It does put a little bit of black smoke out as you hammer it down getting on the hiway but not excessive. No codes check engine lights....

Any thoughts? Ideas?

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Do a search here about sticking FCA (Fuel Control Actuator) for ideas. IIRC, it can be removed, cleaned, and replaced. Or, you can buy new.
Back to morning brew . . .

 

I will check into it and report back! Thank you!


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Reporting back..............I ordered the FCA from Geno's and it got back ordered so I was not able to install on my vacation. The truck quit having problems and I got busy at work again. Last weekend it had a spell with the idle surge. Didnt drive it this week and was out last night driving and it was running fine. Highway travel and around town. Towards the end of the night when I got back into town at stop lights it would idle as normal and when the light turned green it would almost fall on its face as I pressed the go pedal and then it would catch and pick itself up and run down the street just fine. I got it home and this morning I swapped the FCA. It made a major difference in how the truck ran., Idles much smoother and the rpms go up and down much better. It seems to have a ton more power then before. No surging and no loss of power when taking off from a light. Very smooth. I was amazed at how rough the engine was before and after the FCA swap. Engine seems much smoother and wanting to go now. Will try and report back in a few weeks and see if it continues to be ok.

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I'm glad it was an easy fix for ya.
Still working on morning brew . . .

 

Truck is still running great! No issues. Been watching things via the OBD reader. Its a different truck now the way it runs and drives. Totally amazed at the difference! Will report back in another week or so.


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