95 Neon bogging down, poor acceleration

Hi,
I have a 95 Neon that has been showing the engine light constantly.
The last few days it has been feeling like it is not getting it's gas. However on the way in to work this morning on the highway it hardly wanted to accelerate at all. I think it may be an O2 sensor or fuel pump..if it is the O2 sensor, how labour intensive is it to change one of these? I am getting the impression that the sensor itself is not cheap.
thanks for an input
Mel

its the 02 if you take longer than 10 minutes seek pro help

I had a problem similar to yours my mechanic tried everything and found out it was an intake wire shorting out or something with the intake from when i put my hot air intake in.,.,just tellin you what was wrong with mine.,hope it helps
James