Hello,

About a month ago my grand prix died on the way to work and I had all of this replaced:

-Headgaskets
-Intake manifold
-New sparkplugs & wires
-New battery
-New air filter

Fixed the problem but the temp gauge would get very hot all the way upto 210 sometimes when I was idle at a drivethru or something but go back down to about between 160 and 210 on the guage. Didnt think to much of it.

Now when I am at stoplights (only after driving the car for awhile when it heats up I drive 45 min home and by the time I get to the city from driving in the interstate it is doing this problem) the car will idle weird making a rumbling noise I can feel and the rpms will go from 6 or 700 - 900 or 1000 dropping and raising. I push on the gas slow or fast and it hesitates but once I am upto probably 20mph or so i dont notice anything.

I also noticed this problem first started when I used the AC a few days ago and I turned off the AC and it went away. Now the problem is there wether I have the AC on or not. I am worried my car is going to die on me and I want to get this problem fixed before something happens seeing I need my car to go to work its long distance commute.

Thank you for anyone who can help me what I should get checked out or what I can do myself I would like to get this problem fixed this weekend before I have to go to work on monday. Thanks again Gp forums!

The car is a 1998 grand prix GT model.

Have you checked for any trouble codes?

Try unplugging the MAF sensor on top of the throttle body and see if it acts different.

(Big black plastic square)

Might want to go buy some MAF cleaner too.

what is the maf and how do I clean it?