Rough idle after fuel filter change

[bricole1973]

Hello, I have a question for anyone out there who can point me in the right direction. About a month ago I had my fuel filters changed for the first time. I bit the bullet and had the dealer do the replacement along with an oil change. When I got the truck back it seemed a little different but nothing majorly wrong. I took the truck with about a 6000lb travel trailer on a camping trip the same day and all seemed ok. I got fuel just to top off since it was cheaper where we were. Drove home and all seemed ok still. The other day after driving around, when I would come to a stop with the truck still in gear it started idling pretty rough. To the point where the whole inside of the truck was shaking. I would take it out of gear, N or P, and it would go away. I though maybe I had some bad fuel in there. I drained the water separator, added some diesel kleen, and topped off with diesel from a station that I know carries good fuel. The idle has improved a bit, but it seems to be worse until the engine gets good and hot. I have 11111 miles on the truck now. Any thoughts on what might be wrong, if anything? I was thinking about running this tank of "good fuel" through it before going to the dealer with it. Thanks

[Papi4baby]

I would do that, good fuel and add a fuel additive with cetane improver and maybe something for anti jelling, not sure of the temperatures where you are.

[senix]

yeah I think it is just a coincidence with the changing of the filters, bad fuel.

[96_4wdr]

how much water did you get out of the separator?

more than 1/2 cup and it's contaminated fuel. the water indicates the station tank, tanker truck or fuel depot were contaminated, old diesel that partially broken down loaded with chemicals picked up in a tank that has not been cleaned in a long time that dissolve in diesel

or you got a load that was contaminated with the fuel type carried before diesel; leaded av-gas, heavy heating oil, ethanol gas.

some franchise station owners and independents will buy midnite tanker loads of cheap garbage. most states have no fuel quality testing, only test pumping gallonage accuracy.

fuel will even differ between refinerys. i try to buy from one chain in my region that i've had no problems with.

ever get a bad tank of gas, same concept.

change filters again. add a double dose of diesel kleen

[bricole1973]

Thanks for the replies. I only go two BB sized water drops from draining the separator.

On a side note, although it has been idling rougher, once I hit the gas it takes off like a bat outta hell. So I'm not sure what's up with that either.