Oh yeah, you may want to check your air filter too. Makes a great nest for mice. At least it does on an old Saturn, and many old motorcycles.

 

As suggested, could be gas-throw a can of seafoam in the gas tank. Then there are other tests.....in the attached you'll see some of the test, a can of tb cleaner and be sure the tb and the port noted in the attached can't hurt.

 

I am having the same problem......was there a solution for this?

 

Too many times we never know the "end of the story". I'm going to guess you have another thread on your exact issue?

If not, my suggestion is to start a new one, give all of the details, what has been done, anything done prior to the issue starting, ect.

Oh, and don't let the story "dead end".

 

And now I'm having the issue.

Left the car parked for six days, during which time the weather was well below zero on several occasions. Started it up, it ran well for the first couple of minutes, and as I was gently easing to a stop at a light the engine surged so hard I almost hit the car in front of me. The idle looked high and when I put the transmission in neutral the idle was bouncing from roughly 1,200 to 1,600 rpms. When I got the car back home it was apparently acting normally. Another five days elapsed before I drove it again today, and the idle is all wrong, and even on the highway with the cruise control set at say 72 mph, I could feel the car surging, and the surges were occasionally strong enough to cause the torque converter to come out of lockup.

If the Idle Air Control Valve is the issue, I'm surprised to feel the issue at highway speeds.

 

I had a surging idle in a 1998 4-cyl after being parked for a couple weeks. Didn't notice it at speed, but then it cleared itself up & never did it again.