EGR code

My check engine is not on. But I am having problems going up hills it shifts OK until I'm climbing a hard Hills said it goes from 2000 RPMs to 4000 RPMs sometimes I have to manually shift it. When it's driving on straight roads it's just perfect but it is driving at about 1500 RPMs always tried a EGR valve and it made it run worse. So we took it out. When I tried to EGR valve then the check engine light came on and it was dogging horrible. The only time it really does is if I try to force it up the hill then it will act like its running out of gas. Once in awhile it will not seem to want to start they said the battery was probably getting low if it doesn't start then I floor it and it will start once every 3 months. Change spark plugs and wires and head gasket the other day. Using a lot of gas and if you force it help them Hills and not let your foot off the gas then it will warm up. Like I'm going up the hill and I'm at 65 miles an hour and then it'll just start walking down and I lose speed and if I put my foot on the gas and force it then the RPMs go up really bad. But if at night it seems to run better and I can get up the hill easier if I just keep my foot at a steady gas acceleration it can climb Hills in town on a straight road I don't seem to have no problem is it's EGR valve did I have a bad one or is it Cadillac converter clogged. I also was told the transmission was shot that was 4500 miles ago. I do not think it would still be running 4500 miles later do you. I tell you that night it runs pretty good yesterday I went 15 miles couple slugs up the hill couple times it acted up but it didn't not go it always goes but during the day especially in traffic but I'm trying to force it to go 65 climbing a hill I just struggle and if I force it like I said then it'll drop down like it's running out of gas if I let my foot off the gas or get on a straight level then it's fine. Thank you for your help