Transmission issues?

[ultrabeavis]

I have just recently entered the world of the LS1, i have had a TPI third gen firebird for 7 years so i am not a total novice.

Yesterday the A4 trans in my 99 trans am refused to shift into 3rd and 4th gear. The trans does have a rather extreme shift kit, chirping quite satisfyingly in the 1st to 2nd shift. But it is only 3 months old and seems to be just fine mechanicaly except for having a little too much fluid in the trans case. The strange thing is that if i turn the car off and then restart it the trans problem dissapears. This leads me to beliEve that it is some sort of tuning issue, or possibly too much pressure in the trans case with the shift kit? You can almost force it to change into third, it will rev very high and then slam into gear, but immediatly pop back out to N. anyone had this problem before? I Put a trans in my 89 last year and i dont think that the trans is physically malfunctioning, they tend to never regain thier gears if they loose them mechanically.

Does anyone have any ideas or info, i would be greatful for any tips, i have already flashed the car for codes and its throwing a p1404, dealing with the egr.

I would be greatful for anything at his point.

Chris.