Could be detonation too, does it sound kinda like a can of marbles being shaken around? Have you messed with the AFM at all? My AFM spring got worn out on my old motor and was letting the flapper open to easily at low throttle creating a lean condition. Improper timing could be the culprit as well. Might also want to check your fuel system.

Last edited by Dok; 08/10/07 04:43 PM.
'87 4-Runner--DD/wheeler, 4.3 swap coming soon
'89 Supra--E85 powered 2jz NA-T Swap, 533rwhp 497ft-lbs
'89 Festiva, turboed BP swap powered by megasquirt