This post is probably going to ramble. I want to give as much information as possible to have the best chance of receiving help.
I have a 2011 Ram 1500 Laramie. I purchased it almost 2 years ago now. For the first 6 months it ran beautifully. Then I started having issues that have gotten progressively worse. I’ve been to 3 mechanics, and posted on a few different forums trying to get some help. I live in a pretty small town, so my diagnostic options are limited and its my only vehicle. Most of the auto shops around here are pretty basic. They want to throw parts at it and pray. I don’t have that kind of money.
Sometimes the truck runs great. I can accelerate quickly and drive down one road with full power, and then turn onto another road and suddenly the RPMs hang at about 2k and my exhaust note drones. My speed slowly increases, but my RPM does not. If I hammer the gas pedal another inch down it will wake up and take off like a 400HP engine should. This is usually accompanied by a little pop, I’m assuming from the tailpipe. But its pretty dangerous to do because it jumps from 2k to 4k RPM real fast and the back end gets loose. Its pretty bad when it happens on a freeway ramp.
I seem to notice it more after turning, and when going uphill. It does it in cruise control too. I’ll be coasting along at 70 on a flat road, and when I hit a small hill it will lose 4-5 mph and drone the same tone before gunning it up the rest of the hill. I imagine if it was a little slicker outside it would be dangerous.
Sometimes when I start my truck it roars to life (flowmaster outlaw exhaust) or it sounds kind of weak and muffled. Sometimes it roars when I accelerate from a stop, or sometimes it sounds weak and muffled.
Most of my driving is to and from work (4 mile round trip). I rent a vehicle for vacations usually, because I’m afraid my truck won’t make it all the way there. Last night I took a 150 mile round trip in it. All of the problems I’ve described seemed to get worse the longer I drove it. Like something heats up and makes it worse.
I think thats about everything I can say to describe the problem.
I’ve replaced all 16 spark plugs, cleaned the throttle body, changed the air filter, tried different octane levels of fuel, tried different brands of fuel, ran techron or other fuel treatments through it more than once, replaced the gas cap, which seemed to help for a few days before it started running rough again. I’ve tried two different types of oil recommended for the smooth operation of the hemi MDS engine.
At one point I thought it was the transmission, but a local mechanic said he felt it shifting fine. His theory was that the truck was becoming stuck in 4 cylinder eco mode, but there are two ways to drive the truck without MDS activating and it still does the same thing. I ran it in tow/haul mode, and it still bogs down randomly. I ran it in 5th gear and it still does it.
I have never had a check engine light come on, and the only code I get from scanning is a radio region mismatch for my satellite radio.
My most recent theories are a fuel delivery problem, or an exhaust restriction. But without a trouble code its hard to justify throwing money at an in tank fuel filter/pump combo, or new catalytic converters.
I’m hoping someone out there has experience with a similar problem.