2007 XC90 has random loss of petal response once or twice a week. Will be driving and the engine rpm drops off, doesn't stall but no response to petal at all. Speed drops to crawl and will keep petaling and will finally get petal response back. Time duration is 15 to 30 seconds.There are no codes, my mechanic has replaced the throttle body, petal, fuel pump regulator and no luck. And unrelated, several months ago changed all 8 spark plugs/coils. Any ideas ?

 

Did you ever figure out the problem. We have a 2008 XC90 that doesn't respond instantly when you step on the gas.