429firehawk

I recently had my 4L80E rebuilt with a new non-lock-up converter and had it changed to full manual valve body. Transmission works great but since the installation my car has to idle for about 45 seconds before it will take any throttle at all. If you give it throttle it will almost die. After 45 seconds it runs flawless and will not have any issues whatsoever until you shut the car off again. It does not matter if it is shut off for 5 minutes or 5 days it will still need to run for 45 seconds or so before it will take throttle. Its not a huge deal as i prefer to let it warm up but it is just annoying.

The car is a 2001 Firehawk with a 429 LS3 12:1 compression running on 100ul. It was MAP tuned by Speed Inc.

The transmission was also converted to run full cool all the time. (always circulates fluid to cooler)

I cannot narrow down this problem, have replaced several sensors hoping to get lucky. (TPS,MAP,IAC,IAT)

Anyone have any ideas? I wouldnt think i would have to have it tuned again but maybe that is the case?

Is the car looking for a signal back from the trans that is causing this?

Thank you