So I pulled the secondary butterflys, and now my car sounds like it's got a spark plug that's not firing, and at idle the engine shakes. When I let off above 3000 it back fires (just free reving in neutral) like it never has before. I think I just need to finish the rest of the TB mod, and it'll be okay, but I'm curious as to why it's misbehaving? I set the TPS to 1.031 kOhm at idle, and tried messing with the BAC idle screw, but to little avail.

Also, it runs better with a vacuum leak, which to me indicates a rich condition.

Any thoughts?

Thanks,
Sam

 

I assume you've checked ALL vacuum hoses. I had the same problem after I did it, but I found that I left the 3 rear vacuum hoses off... oops. Also, it sounds like you didn't remove the fast idle cam(?) IIRC. With it still in place, the throttle will catch on it and cause a shitty idle.