93 s10 blazer tranny problems

[cata]

well, i was on my way back from work friday and got stopped at a red light (everything was fine before then). after i accelerated from the light, i notcied a strong thud as it switched into 2nd gear and would not shift into 3rd..

on sunday i drove to get some lunch and it was fine till i started my journey back home. it would accelerate just fine, however it wouldnt even switch to 2nd gear.

my brother says it could be a vacuum modulator, but after i searched i didnt see any problems like mine (maybe overlooked)

any help is appreciated

edit: 4.3 vortec, tahoe edition, 4x4(have no idea what type of tranny it is)

[troy1]

There is no modulator and it is a 4L60E could be the shift solenoids they are cheap pull the pan and look and see whats in there for metal 4L60E have a problem with the bearing failing in the rear planet, oh the EPC could be bad also but that would not cause a no shift but it would cause a hard shift or soft shift do to high/low line pressure.

[cata]

thanks for the input, itll have to wait till this weekend atleast, way too busy to check it out, but just wanted to let you know, ill use your suggestions first

[cata]

UPDATE!!

i took my brothers advice, which was the TPS. i swore up and down that it wasnt cause i had just replaced it with a brand new one just a few months back (if that long). but i tried it anyways.

took it on a test drive and everything seemed to be just fine.

thanks for your input though troy if the problem should persist after driving it for a longer test drive, i shall try the solenoids