Transmission is not shifting properly

chevrolet
s-10

#1

two weeks ago I had A cracked head repaired and the rear u joint replaced in my truck. A 94 S10 with 4.3 litre.when i got the truck back the transmission would work good at times and then at times it would not shift in to 1st gear or passing gear. nor will it downshift. what could have possibly have happened. mechanic denies any wrondoing.


#2

Whatever modality the engine transmits the load or throttle position is corrupted. He obviously disturbed it in the work. I don’t know how it is done on your trans. You don’t report slipping or whatnot, just things that would be involved with improper transmission of this intelligence to the trans (be it mechanical, vacuum, electric, or electronic ).

Did he even look at it? If not, then how in the heck does he know that he didn’t do it. It sounds simple to me.


#3

he hasnt looked at it yet tomorrow i will take it to him. im far from a mechanic can you tell me where i can find this throttle body?