i'm getting rumbling at low rpm.we put a scanner on it<and it came back misfiring cylinders 1357. did a back pressure test on catylic converters <but that came back good.i live in n.y. and go to n.j. once in a while, when i gas up in n.j. the truck stalls 3or 4 tmes after when i come to a stop . it only has 50,000 miles on it. i'm curios if this isproblem is connected. any help?

IGNITION WIRES NEED TO BE REPLACED?

HAS THE WEATHER BEEN DAMP WHERE YOU LIVE RECENTLY? THIS WILL TELL THE TALE ON OLD AND DEFECTIVE IGNITION WIRES.

Changed the wires and plugs , ran good. Reset the computer, drove it and it was ok.shut it off for 10 minutes and the problem started all ocver again. Any suggestions?

Is the Throttle housing are gummed up and dirty? Might be a good place to start and clean it to start with.

no, itall looks good. the engine light stays on again,but the problem seems to come and go more so then not.i'm the original owner,the truck has been well mantained, and only has 50,000 miles on it.

early hemis are notorius for broken valve springs

If it is all the cylinders on one bank it could be a o2 sensor on that bank or as said the early ones do break valve springs.

Swap the coils from the other bank see if the misfire moves

Be carefull. a friend of mines durango started running a little rough and a couple days later it backfired on startup and bent a connecting rod on # 1 cyl. Turns out injector leaked down over night causing the cyl to hydraulic.

Seen that happen on a 4.7 but didn't bend anything. The injectors that were leaking had alot less carbon build up.

My 2007 Ram 1500 5.7 HEMI had a cyl#4 misfire last year. I changed the plugs and then did an oil and filter change. The problem persisted. Sometimes it felt as if I were trying to accelerate with flat tires. I took it to 2 dealers and after 2 weeks of diagnosing, the problem turned out to be with the MDS system. The lifters bleed down during cylinder shutdown and pump back up when MDS is deactivated. My truck had one defective lifter that was sticking OPEN, resulting in not only a dead cylinder but also cross contamination of the intake charge. They had to pull the head to change the lifter, hone the cylinder, install new rings and screw it all back together. Total bill: $3700! Grab the vaseline!

I don't think the 2004 HEMI had MDS.

Right, it didn't. The tech at the dealership said that the engine was designed with this feature built in, but it wasn't implemented until the 2006 model. My point was that the lifter was MY problem. My valvesprings were okay, unlike earlier year 5.7 motors.