I have a 1997 maxima. My engine surges all the time even when in park. I've done a complete tune up on this car. My cavalier did the same thing and it was a throttle sensor. I was wondering would anyone know what's going on.

 

Get a shop manul--hanes will be fine. Pull and codes from the computer. Then go out and test the TPS and the MAF sensor. I bet you will find your problem there. Hopefully it's just the TPS as that's cheaper to replace. Last thought....when you did the tune up you might have knocked a vaccum line off. I did that to mine and the cruise wouldn't work anymore and it idled a bit rough. I went back and found it after an hour of searching and tracing vaccum lines right off of the Throttle body---happened when changing the fuel filter!

Good Luck--

You might want to give a 'shout out' to Daniel B. Martin. He is the expert at tracking these things down.

 

I agree with everything Shumax said. I'll add one suggestion. Carefully inspect the flexible black plastic air duct which conveys filtered air from the air cleaner housing to the throttle body. A crack in that duct might cause, or contribute to, your surging symptom.