1998 Saturn SC2 is throwing P0401 code.

No rough idle, the motor mount was broken. All is well again. Except for the p0401.

I recently had a P0401 on my 99 Saturn SC2 with 110K miles. I replaced the EGR valve but that was not the problem. Then I saw this post that said that the engine idle should increase with the EGR valve removed. My engine did not. I found a clogged port in the throttle body that goes to the EGR valve. The gunk clogging the port was like tar. I removed the EGR valve again so I could blow compressed air from the EGR port and out through the throttle body port after I had used a lot of carb cleaner and rags to clean out the throttle body and the port. I had to remove the air filter duct and then 2 nuts to remove the butterfly valve/ throttle valve. The port was just inside and was easy to get at. Makes sense now why I had Insufficient air flow to the EGR. Just wanted to share that information.

Thanks so much, I will try to do that this upcoming weekend.

Well, That was not the answer for mine.I will keep working on it but thanks for the advise. It sure didnt hurt to do it.