my trans wont shift from 1st to second if I give it more than half throttle, but it will shift normaly if I dont get past half throttle. If I floor it it just redlines until I let off the gas then it shifts to second. It still upshifts and downshifts and shifts to 3rd and 4th normaly. All thats done to the trans is a 2800 stall vigilante and a transgo shift kit. Is this my two to four band or something else. 1995 z28 4l60e its been 2 years with the converter and shift kit with no problems until now

 

Tps