if my 2006 chevy impala stalls to accelerate above 20 mph and check engine light is on, could my fuel pump be going out?

Sounds like you have a bad Throttle Position Sensor. You may want to give the throttle body a good cleaning also. THROTTLE BODY CLEANING PROCEDURE Remove the air cleaner outlet duct. CAUTION: Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury. NOTE: Do not insert any tools into the throttle body bore in order to avoid damage to the throttle valve plate. Inspect the throttle body bore and the throttle plate for deposits. You will need to open the throttle plate in order to inspect all surfaces. NOTE: Do not use any solvent that contains Methyl Ethyl Ketone (MEK). This solvent may damage fuel system components. Clean the throttle body bore and the throttle plate using a clean shop towel with GM Top Engine Cleaner, P/N(NNN) NNN-NNNNor AC-Delco Carburetor Tune-Up Conditioner, P/N X66-P, or an equivalent product. Install the air cleaner outlet duct. http://www.youtube.com/watch?v=zUV4nXc-pXU

Same problem mine sat for two years tho. I cleaned valve body and didnt change anything. Did you have any luck?

ust purchased a used Chevy Impala 3.4 liter. I am having problems with acceleration. When I came to a complete stop and then accelerate the car it hesitates and jerks between 0-25 mph. The engine breathes heavy and the rmp fluctuates. I am not displaying any check engine lights. When purchasing the car I noticed the transmission fluids were 1.5 QTS low. I added fluids and the colors is red and I have no leaks. I believe it has some to do with the fuel system. I poured some fuel system clean in the tank to clean the injectors and filter and went to Walmart to have injectors blown out. It has help a little but still having the problem. I am about to take it to the shop to have them look at the throttle body sensor, fuel regulator, MAF sensor, MAP sensor and check for vacuum leak. Is there anything else that I should have them check to solve the problem? Has anyone else had this problem?

Julia, I bet the reason why they got rid of the car is because of the acceleration issue. I checked numerous forums on the issue. Apparently just about every Impala comes down with this issue. Not one person has come up with a definitive answer on the cure. They have changed everything under the sun and nothing seems to do the trick. I found one post where someone had said they knew a guy who changed out the camshaft sensor and that seemed to fix the issue for him. Like you, most people that have this issue, do not have the check engine light on. It's pretty much a shot in the dark on what part to change out. It doesn't seem to be one of the easy parts. People always start by changing out the fuel filter, plugs, wires, MAP sensor, MAF sensor, EGR, with no change in the issue. One guy even tore down his throttle body and cleaned it until it looked new and still had the same issue. If it were my car and after reading all of the forums with no luck, I would change out the TPS sensor and the Cam sensor first. People seem to change out all the easy sensors with no luck on fixing the issue. Even people that bring it to the dealer have no better luck. Since there's no check engine light, the dealerships don't want to waste hours on actually figuring out what the problem is. Please keep us posted on your progress.

Doc Dave say replace ur catalytic converter or hill Billy take screw drive sleghammer and put a hole it stop

Changed absolutely everything.. come to find out ... I bypassed the security system and did a reset on the car and it is fine now. It’s problems with the security system.. after while it messes up and once that happens it shuts down something wth the fuel system and that causes the car to not work. Hesitates, dies out, or won’t drive...ect...