I just got my car back from the shop, 02 dodge intrepid and tonight the engine light came on shortly after starting (been running fine since Saturday).

When I try to speed up at around 3000 - 4000 RPM the engine stutters and the car shakes a bit like it wants to go but it can't. I put the car in neutral and reved it up a bit and same thing.

Now last week I had the Timing Chain and Water Pump replaced and a mess of gaskets, hoses, belts and stuff. It ran fine no probs for a few days and now this?

Any Ideas? I need to know generally what is going on so I don't get screwed.

Take it back and tell them they screwed something up... assuming the problem started immediately after getting it back from the shop, and the problem wasn't the reason you took it to the shop in the first place.

Is it like it's hitting the rev-limiter (a sharp/instant loss of power), or is it like it's barely making it to that point, and it has something else holding it back?

Problem happened a few days after getting it back. Went in thinking it was a head gasket but turned out to be the water pump and timing chain needed to be replaced. (Water pump is burried in the engine and is a major under taking on this car)

The engine has no problem getting up to speed, but feels like it is being held back if you give it too much gas. It feels like it wants to go but can't. If you slowly accelerate you can get up to speed, just not if you give it more gas.

I would take it back to the shop as it sounds like something wasn't hooked back properly.  Anything from a Throttle Position Sensor failing to a simple Vaccum Line coming loose can cause this hesitation at speed.  Also, the simple code reading done at the auto parts stores can be misleading.  Sometimes a problem in between two sensors will log a code showing the two sensors to be bad or failing when in fact it's because something else is changing the dynamics of the cars performance........ie: Bad Gasoline, clogged injector, etc.

If you want too, raise the hood with the motor running and listen for a "sucking sound" as if air is being pulled in to a hose.  Try it both at idle and with someone running the rpm up at bit.  If you find a hose loose and sucking air, try and find where it should attach and you may can fix it without going back to the shop.  

Finally, if the Fuel filter is starting to stop up and needs replaced it will indicate this need first at the higher RPM's because it can't filter the higher flow of gas.  If you ignore it,  finally it will start to stall and eventually leave you sitting.

I hope some of these ideas might help.

Good Luck,

Pinz

You've got to know the code, that will lead your troubleshooting.  If the engine is being held back at a certain RPM regardless of how hard you accellerate it sounds like a flow problem.  Air, exhaust or fuel.  Could your cat be plugged?  If you have an O2 code that would be a clue.  Could it be a missfire?  Not sure where the crank position sensor is located on that car but if it's up front when the pulled the front end off to replace the belt/pump they could have bumped it.  

UUghghhh! Modern cars/trucks... So much stuff to rehook when major work is done... I bet it is something not hooked back up properly...

Probably not the timing chain as the engine would run very poorly through all rpm ranges or slam your valves... Nor does the water pump have anything to do with your problems...

My expereince with mechanics from working along side them (parts): many are not the brightest nor have the best memories... Since your car sat so long untouched while waiting for parts/tools, I suspect the mechanic had a tough time figuring out where everything hooked back up. It is one thing to tear down and then rebuild while very part/wire/connector/tube is still FRESH in your mind and quite another after several days to a week has gone by.

This is why I love digital cameras when doing something major... but I've never seen a mechanic use one.

Rmpl

Might be some kind of interlock with the tranny in neutral.  Normally there is an engine cutoff with the engine in neutral as to not overrev the motor.  looks like some sensor is broken/dis-connected.

MIght wanna run this across the guys at www.dodgeforums.com .

My dakota did something similar but it was teh crank trigger sensor.

first of all...timing BELT.....not chain..second.. these engines are not interference engines [valves will not hit pistons if belt snaps]

Now...did you have the tensioner replaced?.....these have a history of going south...especially after just replacing a timing belt.  The tensioner hold constant tension on the timing belt to ensure it does not skip a tooth or two.....which is the likely scenario here...the timing belt is not correctly set up on time..It runs but very low power....either the tech who did the work screwed up and set the belt a tooth or two off.[you would have noticed that right away] or the belt has jumped and the timing is incorrect.

It sounds like you are going into limp mode....how is your oil pressure when the vehicle is at idle?

I also think the cam timing is worth looking into. Vacuum leaks show up at low RPM, not higher speeds. If you have a distributor take a look at the timing there also.
Oh, check out the fuel filter/fuel pressure too.