I just bought a used 2003 Ram Hemi 4 wheel drive. It has headers installed and thats the only upgrade. For having 345 horse and all that torque it sure doesn't move very fast. I haven't beat on the truck that much but one day I punched it and that thing took off like a rocket. It actually acted like it had some *****. And when I punch it any other time it just feels like its obstructed, fuel, exhaust, intake?? I just put a K&N filter on it with no noticeable acceleration. Any suggestions as to why I felt all that power one time and one time only? But now it feels like its only got 200 horse?

 

Welcome to the forum.
I would start with as good tune up. New copper core plugs and plug wires. Clean the throttlebody and perhaps change the PCV valve depending on the mileage.
I also highly recommend running 89 octane fuel. It is recommended in the owners manual and can save cylinder failure down the road from detonation caused by 87 octane that can't always be heard.

 

Catch it where it can't downshift and it'll be molasses. Stand on it at 30 or 60 mph and you should smile.

For some reason they picked 5 useless gears for our transmission. It'd be great for a car but there's no reason for a truck to reach 70 in 2nd gear. If they re-divided the first 4 gears so they each were more aggressive it would make the truck a lot more driveable. There's always 5th gear for comfy cruising.

 

The truck has had a recent tuneup, as far as a pcv valve im not sure and the TB prob hasnt been cleaned either. I just noticed that one time I stomped on it it really felt like a truck but never again has it done it. I will try those things

 

Definitely do a complete tune up. You don't know what was changed out or when. Plugs, wires, oil, coolant, filters, hoses, belts, flush brake fluids, change transmission fluids and filters, change diff oils, brakes, rotors, inspect front end suspension components, ect.

 

It doesn't miss out or run poorly. It's just the acceleration is not like I think it should be.

 

could be plugs, wires, air filters, clogged cats, vac leak, ect

 

I used to own a 2003 Offroad edition with the 5.7 and I got it BRAND NEW. I was surprised at how little of the 345 horses were actually making it to the wheels. I actually got beat playing around "racing" my wife while she was driving a minivan... yes, a MINIVAN!!! I could never get the tires to even chirp from a dead stop. I had to trick it into breaking them loose by letting the truck roll at about 5-10mph before stomping on the throttle, then it would chirp but that was about it.

I tried a few of the suggestions from the forum like the zip tie to take up slack in the throttle cable and pulling a pin from the wiring harness to help with the torque control. I even had the functional cold air ram hood (fiberglass) installed. I eventually replaced the muffler with a FM. Even though it sounded better, it didn't move any quicker. I never tried a programmer on it, but even without one, I was disappointed with how "weak" my new truck with a HEMI engine actually was.

I couldn't really do too much to that truck because it belonged to the contractor I slaved for at the time. It was supposed to be "my" truck, but I knew better and when I eventually left the company, I had to leave the truck. My 2005 I have now with or without the SCT programmer could've kicked its @ss without even trying! The truck may have been a lot better if I had used a programmer on it at the time, but I never did. I didn't want to spend too much money on it when I knew it wasn't really mine as my former employer tried to convince me it was.

The guys on this forum will be able to help you. I have learned a tremendous amount from them and continue to do so.

 

Mine will roast the 305's if I want it to. I've fared pretty well in all the little "contests" I've engaged in, including anything from a late 90s Maxima to a new turbo Volvo. I didn't get the truck to be my fast car but it holds its own. As long as I don't need to go anywhere from a 40 mph punch it's fine.

All I've got is a programmer, the removed wire mod, and an intake. Exhaust is stock.

To the OP: Check your glove compartment for a label to see what rear gears you have. 3.92s are a must if you want a big truck with big wheels to go anywhere.

 

I just checked and I do have the 3.92 axles. I have headers on it which make it sound a little nicer but no performance that is noticeable. I have high flow converter. Where is the pcv valve located on the truck? And also what is that wire that u guys are removing and what does it do?