96 XLT 1-2 Shifting Problem

[fireball34]

Hi, I have a 96 Explorer XLT, the thing will not shift out of first into second without letting off the gas. Once you get it shifted into second it operates perfectly. I have replaced the fluid and filter and tightened all the valve body bolts. I suspect an electrical or computer problem, but you guys are the experts and I wanted to get a professional opinion. Any and all help will be appreciated.
Thanks Guys

 

[marragtop]

Have you pulled the codes yet?

 

[fireball34]

No Not as yet, Dealer wants an arm and 2 legs to check it. Any suggestions for how to get them cheaper.