My '90 GXE is not down shifting when mashing on the gas in Third/OD..

The car was fine until some injectors went bad a few months ago and I let it sit until I could get around to tearing the top of the motor down yet once again

Anyway,.. I changed out the injectors and she's all back up and running now,.. but won't down shift when I mash on the gas in Third or OD,.. or 2nd for that mater (Automatic Trans.) .. I can manually shift through the gears,.. but she won't pop down on her own. Although when I slow down the trans shifts down normally ...

Any ideas or suggestions?... in the old days this was an easy diagnosis... Vac. Modulator ,... but I'm not even sure what's on this one,.. solenoid,.. vacuum relay??..

Thanks in advance,
Rick

 

I had a post on this a few weeks ago...no help with it. :P
Get yourself a multimeter and test the throttle position sensor. Also, there's a way to run a self-diagnosis on the TCU to find any error codes, it's somewhere on this site.

 

were is the tps and what should it read on the multimeter??

 

could be the valve bodies inside the transmission aren't flowing correctly and are causing it to not want to down shift when you wot to get that acceleration to pass or get on a highway from on ramp or so on. Can better explain it when i read in my book i used in automotive technology tomorrow once im at home.

 

Turns out "I" forgot to hook up the TPS and another connector right there in front,.. DOH!!!!... working fine now

 

Lol good thing rebuild would of been a bit spendy.