I bought my truck in April. 2003 Hemi Single Cab. The last 2 months I have noticed that between 1st and 4th gear the engine seems to be working really hard to accelerate. My RPMs go up to 2k and don't change at all between shifts until the torque converter kicks in at 4th gear, then it goes down to 1500 and up when getting faster. I have been noticing that my gas mileage has gotten slightly worse as well. I have a K&N CAI, Flowmasters, and a DiabloSport Tuner 93 tune.

I am changin my oil tomorrow, which I change regularly, and I might need to change some plugs but still wondering what else might be casusing this problem. I took it to a transmission shop and they couldn't find anything wrong with it. No codes thrown and a 30 year trans expert didn't feel anything different in driving it but I know its there. HELP!!!!

 

maybe you just not flooring it like you used too lol at least thats what happened to me

 

when you took it into the tranny shop did you have them change your filters and fluid, if not try that, next option is when was the last time you had your fuel filter replaced, and maybe try cleaning you fuel injectors out,( barrymans b-12 carb and chem tool cleaner works great for that one) and pull one or 2 of you plugs and they look...

 

When also was the last time you changed spark plugs and wires? Maybe a compression check on each cylinder would help. It could be you are losing power from just a worn out engine.

 

plugs would be my first guess also how many miles are on the truck? it's possible your cat converter is getting clogged maybe time for a new one. Normally it will throw a code, but i did have a car that had exact same symptoms you speak of. We took a bar and smashed out the honeycomb and all of sudden that car had go like no other.

 

No fuel filter unless you drop the tank as far as I know.

 

Fuel filter is lifetime, pretty much. Plugs, PCV valve and TB clean, pronto.

 

Thanks guy. I gotta get my Cat replaced. Damn thing is completely stopped up. Thanks for the responses.

 

When you get it removed and replaced, be sure to take it home with you so you can sell it to someone here who may want to hollow it out or you can maybe sell it to salvage yard for some change.

 

Well went to the shop to get it replaced and the guys could not find anything wrong with it. There were no signs in all the tests that it was the cat. They suggested a couple things...fuel filter, fuel injectors, or fuel pump. My trucks is not stalling or knocking or anything else but having a lack of power when the pedal is put to it. I feel that if it was a fuel related problem, there would be some kind of other symptom. What is it? my mileage is getting worse and I am still not throwing any codes no CEL.