Misfire problems and EGR code

I have a 97 GP GT with about 211,000 miles. After having my transmission replaced, for the first time, and having new plugs put in, it was running fine for about three months. The other day the car started to put and seemed to have a loss of power. Now the check engine lights keep blinking and then goes off for awhile and starts back again. The car starts fine but surges periodically. I am hearing a roaring noise when I begin to accelerate but this stops at around 30 to 40 mph. I had the codes ran an insufficient flow on the egr and random misfire are the only two that show up. The gas mileage is horrible. Can anyone help me with this.

I have a 97 GP GT with about 211,000 miles. After having my transmission replaced, for the first time, and having new plugs put in, it was running fine for about three months. The other day the car started to put and seemed to have a loss of power. Now the check engine lights keep blinking and then goes off for awhile and starts back again. The car starts fine but surges periodically. I am hearing a roaring noise when I begin to accelerate but this stops at around 30 to 40 mph. I had the codes ran an insufficient flow on the egr and random misfire are the only two that show up. The gas mileage is horrible. Can anyone help me with this.

it costs about 165 bucks to replace it yourself. its very easy to do but one thing to remeber that you need to get a pipe cleaner and clean everything out insde the place where the EGR goes. you need to make sure all the black stuff comes out. if you need some step by step instructions let me know its very easy. but make sure to get the old gasket off and replace it with the new one they give you. any other help just reply back and ill be glad to help. as far as the misfire code its a pretty common thing with the 3800 go get the code erased after you replace the EGR valve. it might go away if not you might need to take it in and get it checked on. good luck

check the PCV valve and make sure both o-rings are intact. There is a large o-ring at the top of the pcv housing and a small black one around the PCV itself. If either of these are missing, it can trip an EGR code. The PCM uses the MAP sensor vacuum signal to determine EGR flow (the MAP clips to the top of the pcv housing).

If you have the odb-ii DTC error codes post them. The SES light blinking is a confirmed misfire detected by the PCM. What brand spark plugs did you use? How about the plug wires, were they replaced?

If the EGR flow error code is P0401 then I agree with Rich's suggestion.

If the EGR is stuck open it will definitely cause misfires too. If stuck open it will probably be a carboned up or flaky EGR valve so I agree with the other post on that avenue.

Well guys. I had the car checked by a family member who is a GM mechanic. He says that he will check it out for me. So far, he has pull the motor out because of the high mileage and poor care that the car received before I got it. He wants to break it down to check for everything so that I can have a more reliable ride. His initial response was the exact things that you guys mentioned. He is going to do this for free because he says he does not want his nephew giving up on GM products since I have had a considerable amount of problems from the car. Thanks for all the help.