94 Ciera running rough

My girlfriend has a 94 Ciera with the 2.2L 4 cylinder with about 140,000 miles. The car just lately started to idle real rough (the whole car shakes). When you are driving you can push the accelerator all the way to the floor and there is no acceleration and the engine rpm doesnt increase. This is an intermittant problem that happens about 50% of the time. The fuel pump is working (can hear it) but it seems louder than normal. I am at a loss where to start. The plugs and wires are only about 2 years old so I dont think it is them. Anyone have any ideas? Thankyou

Welcome to AF, this could be an engine misfire or bad fuel pressure based on your description. Check for spark at the 4 plugs, pull them out see if any look like they are not firing, if everything seems ok in the ign. system, check the fp next.

Thanks for the help. We are going to see if there are any fault codes tomorrow and go from there. Could a bad transmission cause this? The transmission was changed 3 years ago due to a stalling problem when the car was put into drive. Thanks for the help.

The tcc solenoid in the trans if sticking, would cause a stall as the car slows down, like not disengaging the clutch in a std shift.

What you describe as intermitten makes me sure its your fuel pump. reason, loud pump, shitty acceleration. The pump is ok sometimes because it's condition worsens as it heats up. Running low amounts of fuel in the tank will increase your symptoms even more.
The fuel lubricates and cools the pump, so when you put in your new one, try to keep it above a quarter tank. The pump armature and bushings are likely worn from age and heat.
When you change the pump be sure to install a new fuel filter... very cheap.

We had the fault codes read and it gave an egr valce, tcc solenoid and a 3rd gear switch. I replaced the egr valve and it didnt help. The car is messing up at around 20 and also 40-50 mph. You can also hear backfiring at times. I have heard that you can unplug the tcc solenoid and still drive the car. Is there any truth to this. Thanks