Judging by the amount of crud I've seen in 3vze manifolds and throttle-bodies I wouldn't be surprised if your throttle position sensor (TPS) wasn't gunked up. I've had the problem on 22RE engines. I was able to solve it with solvent. A couple of drops of Gumout carburetor cleaner in where the shaft enters the sensor had mine working again. Go easy though. Don't use more than a small amount. No telling what it would do to the internals of the sensor if it got to far in there. -- Matt

'89 4runner SR5, 3.0, auto (fun)
'93 xtra cab, dlx,3.0, 5spd (work truck)