Engine Mechanical problem
1999 Oldsmobile Alero 6 cyl Two Wheel Drive Automatic 92,000 miles
I have a 1999 olds alero, with a 3.4L engine and had the Intake Manifold Gasket replaced, along with a tune-up. After I got the vehicle back, I noticed a rough idle. It starts just fine and runs fine at highway speeds, but just has a rough idle. I made sure all the plugs were tight along with the vacuum lines that I could see were connected but nothing. Obviously I am going to take it back and see why it is doing it. Right now the shop is closed but was wondering what would have caused this problem?