I have a 2000LS1 SS engine . The tranny is a 4L60E converted to a 4L80E The computer has been reprogrammed , the exhaust has been modded to
recognize one cat. The other cat has been taken off. The air intake has been modded to accept a KN cone filter. The MAF is the same.

Now for the problem. When the engine is idling, there is some surging going on
in the engine. I can't tell if it is an electrical problem? While the engine surges the impeller in the fuel pump is surging insync as well.

Does any body have any experience with this?
BTW the engine is installed in a jeep. Thats why all of the above mentined mods.