My 98 2.3CL 5-speed studders a little when I give it gas and the AC is on. It last only a couple seconds and feels like it might stall but then it goes away. When the AC is off it drives perfect. What is making it studder?

 

It's likely the Idle Air Control Valve and throttle plate are very dirty. This prevents the IACV from correctly compensating for AC load, and your idle may be too low w/ AC on. This leads to stumble when you try to accelerate.

Fix is to throughly clean IACV and throttle plate w/ throttle body cleaner. Don't soak the IACV solenoid winding w/ throttle body cleaner as it could damage the winding. Make sure IACV is working correctly. It's a solenoid valve and you can apply 12V directly to observe the valve close quickly, if working.

good luck