Yeah. I want to confirm that. My '01 was doing the exact same thing. The dealership replaced the IMG under warranty and it runs great now. Modifications should not affect warranty unless you installed a supercharger or something else that affects compression. By law, your 100K drivetrain warranty is not affected by aftermarket parts or mods unless they can be directly linked to the failure. If it is over 100K, then several on the board have done good write ups on IMG replacement, (Doug - username BANSIL). When it gets worse, your CEL will code, indicating a vacuum leak. But, it may go a long time without the CEL indicating a problem. The dealership could hear the vacuum leak on mine, but mine had also coded after I let do a few hard stalls. The CEL turned off again, but the code stays in the computer for quite a few cycles.

Pete