Dodge Repair: dodge neon motor, double overhead cam, dodge neon

Question
I have a 97 dodge neon that i just put a used motor in.  I have chenged the plugs--new timing chain, etc and have had everything hooked up for about 3 weeks but still trying to get the timing right.  it starts but sounds either fuel rich or sounds bogged out when i accelerate the engine.  I also have used a scan tool with little help with that.  I cant get the timing right it seems...i change it one degree or another even in a fraction of a move and sometimes that seems to help but then when i get the parts back on the motor aftger the timing is set--then it seems that the timing has moved again by the time i start it up--I need this car to get to work and ive hit so many brick walls trying to get it to run--would you have any ideas or suggestions for me to try?  I have also tried resetting the computer by doing the clicks of the ignition with no luck--any suggestions would really be appreciated and thanks for your time
Kevin

Answer
Kevin,

Do you have the Single or Double overhead cam engine?
The ignition timing is controlled by the PCM, How are you
changing it?? Or are you playing with the timing belt??
If you have moved the timing belt, you may have bent a
valve.  
Have you seen this engine run before you put it in your car.

I can think of alot of things that may be causing your trouble.  
I really hope the timing belt was installed properly the first time.  If it was out, I will bet on a few bent valves.
I would confirm correct t-belt installation then disable the engine, remove the plugs and do a compression test. If all the cylinders are good then
check the fuel pressure, and make sure the exhaust is
not plugged.

Also, make sure the firing order is correct.