RPM jumps at start up???

[disel78]

I have a 98' Qx4 with 136k miles recently when I start the car in the morning or even there after within 2 sec of it turning over the rpms go up to 2500 back down to 1000rpms fluctuating between each other like it's revving up and down then goes away with in 10 seconds of starting.It was happening ever so often but recently it is now happening a lot more. Tends to happen at first start but has been doing it anytime it wants now.

My mechanic whom I trust completely is stumped. He has mentioned cleaning the MAF and running sea foam in the gas to clean the injectors out, both have been done but still having this issue.Oil and all maintenance is done on time and throttle body is cleaned every oil change

Any ideas or thoughts would be great
Modified by disel78 at 2:14 AM 12/11/2009

[disel78]

Come on anyone????? 30 some views??? COME ON NOW?