Check Engine Light Around 50 mph

[RoninJedi]

95 Tahoe. When I'm driving and get around 50 mph, my check engine light comes on. But no matter how long I drive it, if it doesn't go up to 50, the light stays off. I don't notice any change in the way it drives when the light comes on, and if it matters I took it through emissions a couple months ago (it was happening then, too) and it passed like a brand new truck.

Did some Googling and found nothing. Thoughts?

 

[Slammed]

Read code post it or Google the code

 

[lesterl]

Change out the base gasket to the TBI.....

 

[lesterl]

Pull the code... Code 32?

Jump the upper right 2 most pins on the diagnositc connector under the dash with a paperclip or something, turn ignition on but dont start it, CEL will flash 1x pause 2x long pause, 1x pause 2x long pause, 1x pause 2x long pause, new codes will flash out 3x each this series of codes will start with the 12 and end with a 12.