XC90 Idle Surge
 

I recently took my Volvo XC90 (105k miles) into the shop for a severe idle surge. The dealership recommended cleaing the throttle and replacing the mass air flow sensor. Total cost about $2k. I took the vehicle for a second opinion, and the local mechanic agreed that replacing the airl flow sensor would solve the problem. I agreed, and for about a week the engine idle improved substantially. Now, it is back to as bad as it was before. The cost for a throttle cleaing is about $700, and I was wondering if anyone else had any experience with this problem before I spend the additional money. Any help would be appreciated. Brad