wtf did i do?
 

ok so i have a 98 z28 a4. its got jet hot lt's and used to have a ps ory with stock catback. today i decided that the stock exhaust just wasnt cutting it so i fabricated a true dual setup using some magnaflows. once i got everything done i took the car for a test drive and the car ran fine but the mufflers were to low and would hit the floor. so i got the car back up in the air, figured out how to place my hangers so the exhaust would be tucked up, got it back down on the ground. i turned the car on again to go for a test drive when i put it in drive it engaged really roughly. i pulled out on to the street and floored it in drive. the car felt really sluggish and shifted hard into 2nd at roughly 2800rpm. car shifts into 3rd and 4th at the same rpm regardless of being WOT. this is my daily and im clueless as to whats going on. any help would be appreciated. :bang::bang::bang::bang:

........

make sure your arent throwing any codes...
could be something simple as you accidentally unplugged a sensor, or possibly just forgot to plug one back in in the process of doing your exhaust...

really sounds like the trans is in abuse mode or limp mode because of an SES type issue..
sometimes the SES wont show up unless you look at it in a code scanner.(which you can get a free scan at any auto parts stor)

well i put a scanner on it and its throwing a code for the tps low voltage input and a code p1639. i replaced the tps and im still getting the same codes

find out what your actual TPS voltage is..... at closed and WOT positions


and check for melted wires...

which wire in the tps do i have to tap into to check voltage?

Ok so i found the pinouts and checked continuity to all the tps wires and theyre all good. Anything else i can look into or am i needing a new pcm?

got it fixed! turns out i grounded out the 5v reference wire that goes to the fuel tank when i was bolting the exhaust hanger to the floor. all better now. thanks for the help. appreciate it.