[Dober89]

The intake manifold gasket can cause the engine to run rough because its leaking and pulling in air that isnt accounted for. When mine went the car would always stall when I put it in park and sometimes when I started it up also. To check for a leak, take off the plastic engine cover and spray some carb cleaner around the lower gasket near the cylinder heads. If the engine sputters when you spray a certain spot then the gasket is leaking and you should have it replaced.

I just replaced mine for the second time at 85k miles. They are made from a very brittle plastic and they dont hold up all that well. The first time it was replaced it had about 55k miles on it.