P1131 Code For A 98 Contour 4 Cyl.

While in park, my car will idle normally and then after a few seconds
it will idle extremely slow and begin to shudder as if it was going to
die on me. It happens worse if I happen to have the AC going. Check
engine light was on so I checked the code and got back P1131. What
gives? I've done some searching around and have only gotten mixed
signals about my o2 sensor or my fuel filter or a vacuum leak. How
can I check those and how much would it cost?

Thanks!

On Wed, 25 Jun 2008 20:44:38 -0700 (PDT), somabrandmayonaise
<somabrandmayonaise.RemoveThis@hotmail.com> wrote:

>While in park, my car will idle normally and then after a few seconds
>it will idle extremely slow and begin to shudder as if it was going to
>die on me. It happens worse if I happen to have the AC going. Check
>engine light was on so I checked the code and got back P1131. What
>gives? I've done some searching around and have only gotten mixed
>signals about my o2 sensor or my fuel filter or a vacuum leak. How
>can I check those and how much would it cost?

Have you tried cleaning the MAF sensor? I'd begin there before I
started replacing things.