Ok.. So I have read several threads, been to several shops and can't afford to keep taking my truck anymore. I have a 2003 Dodge 2500 5.7 Hemi. From what I have gathered, I'm not the only one that has had a problem with these trucks. This is what I have going on... When I have my truck in park, drive or reverse the RPM's just start surging big time, truck starts loping like crazy. If you just let it set there a minute it will smooth itself out but as soon as you go to take off or go up a small incline it starts bucking and jumping but when you reach a higher rpm it will smooth itself back out again. I notice when it does the the fuel will smell real rich like it's almost flooding. It really does this when I am pulling a horse trailer at speeds about 55mph, starts jerking even with OD off. It's weird because one week my truck may run just fine then the next week it may run horrible. This is driving me insane!!! Here is what I have done so far, I'm pretty green but have learned quite a bit just messing with this crazy thing. I have..

*changed Plugs and wires.. no improvement
*Changed Crankshaft position sensor..nothing
*Cleaned the throttle body several times...no improvement
*also checked pcv valve and seemed to be ok.
*O2 sensors replaced
*had Catalytic Converter removed thinking it was stopped up.
*I did disconnect the battery for 30 min and it ran better for a few days before it started acting up again so I took it and had computer updated thinking that might be it and that didn't help at all.

When it was at the shop they did say they couldn't find a vacuum leak. It just puzzles me how it doesn't do it all the time, but it def will under a load. I figure I will start with the smallest things first, I read lots of suggestions but they never posted the outcomes to them... PLEASE HELP!!!

The ideas I have to start with is Camshaft position sensor..could the whole throttle body be bad? Bad APPS? MAP Sensor? Injectors? Broken Valve Spring? I have done the key test and my truck has no codes. It did have misfire codes before we changed ignition coils but those are cleared.

Sorry for long post just wanted to get everything in

 

Sorry to hear about your woes.
My guess would be for a inexpesive fix try grounding the throttle body first.
There are a few threads on
this and it's easy to do and
costs no more than 10 bucks.
The throttle position sensor may need recalibration.
Easy to do...with the key in the on position truck not running. Press the excelerator to the floor very slowly 30 sec down 30 sec up and see if that works. If it doesn't it may need to be replaced.
I know that the 03 Hemi's had valve spring issues with them wearing out or even breaking that may a possible suspect.
Start with the throttle body and hopefully it will work for you. It can' t hurt.
Good luck.

 

I'd start with the camshaft position sensor. They can intermittently work when they start to fail. Since you've already done o2s and the cat and it still runs a bit rich and tough at times, the csp sensor obviously affects the timing and when it starts to fail it could do everything you're describing. Kinda weird it hasn't thrown any code ever but that's what I'd try. Good luck

 

Hey thanks for the response! I have tried the recalibration and that didn't help. I got a camshaft position sensor today and fixing to go try that....fingers crossed but i highly doubt that will work....

 

I hope you are right, fixing to put the sensor on... just have to figure out where it's located. Anyone have a diagram? Is it near the crankshaft position sensor??

 

hows the battery? If the battery is going bad it can cause crazy things to happen.

 

Just put a new battery in it

 

ok.....so I am having some trouble.. I can't find the Camshaft Position Sensor... I found a sensorof the front of my engine that is above the oil filter..what is that?? Anyone know where it is PLEASE HELP.. this sensor I found doesn't look in good shape at all.. could def be the cause if it's an important sensor....

 

ok..so i finally found the camshaft position sensor.. had a time getting it out!! shew! The other sensor I said that was nasty was the oil pressure switch sensor. Don't guess that matters to much. I went ahead and cleaned the throttle body again while I was at it, wasn't very dirty at all. Bout to go for a test drive...lets cross our fingers that it was the sensor.. oh and I forgot to add that this morning I filled up with 93 gas and added a bottle of lucas injector cleaner. So far it has improved fuel mileage but that's all I have noticed. Will keep yall updated!

 

do you have a tuner?