I got a problem with my car. It started about a month ago but now its gotten really bad. It first started to hesitate like if it had a electrical faiure from 1200rpm to 2000rpm then it would go away. I would change the sparkplugs and it would go away, but it got worse and the last time I changed the s.p.(last week) the problem stayed.Now the problem sounds like if a valve stayed opened and it loss compression.I took it to saten and they said that it was the egr valve. My question is if this could be causing the problem. O now it hesitates all the way from 1000rpm to 3000rpm. This really sucks.

I can't see how the egr system would cause a hesitation like that. I can see how a fouled o2 sensor or bad spark plug wires would though...

The o2 sensor is good cause the rich and lean gauge reads well. and i checked the s.p. wires for conductivity and they were fine

You might try putting a volt meter on your MAP sensor and check to make sure that its sending the right voltages at idle and at WOT also. At wot its supposed to be 4.5 volts and I can't remember off the top of my head what its supposed to be at idle...

I disagree with the idea of testing map sensor ....If it was the MAP sensor there would be a check engine light on... I would check the egr valve first... Somtimes when those emission parts go bad it messes the engine up. If they said that, then learn how to check it and start there. One question would be, do you have an erratic idle?
If you know where the valve is located take it off to test it...all you have to do is make sure the plunger devise is still working properly. if it doesnt plunge right, use some cleaner and clean it up...also if you have a compressor you can pump it up to about 20psi and put it up to one hole and cover the other and blow in to it to make sure no air is leaking then uncover the one side and make sure air passes threw.

when the car is cold there if no erratic aidle, but as soon as it warms up, there is a slight jump in the rpm needdle, it isnt that bad but there is a notice in change. Anyways thanks for all the imput.

Well I don't know if you are familiar with the problems that us turbo guys get with the MAP sensor voltage clamps, but it is similar to his problem. There is a hesitation because the MAP sensor sends an incorrect voltage and the car will not throw a code because the voltage is not exceeding 4.5 volts. Instead, the voltage is too low for the amount of engine load and throttle position. The reason I doubt that the hesitation has anything to do with the egr system is because many people (myself included) have completely removed the egr pipe without getting any hesitation like that. I suppose its possible to have the egr solonoid allow exhaust through when it is not supposed to be, but I still doubt that would cause a hesitation like the one that he's describing...

Where is the map sensor in my engine?

its on the far left top side of the upper intake manifold as you are looking at the engine from the front of the car.

Is there a fix with the map sensor or do i need to buy a new one?