90 Ls Slow Rpm Drop When Changing gears

Hi guys, I just bought a 90 Ls Integra last week and when im driving it everytime i change up a gear the car keeps revving for a second (like im still pressing on the throttle but im not) and after a second the rpms drop and i can proceed the the next gear to do it all again. what i have noticed is when engine is cold its normal but as soon as it warms up its there.

So far ive checked for vacuum leaks and theres none, cleaned the iacv and tested it and it works, cleaned the fitv and tightened it all the way down, tested the coolant temp sensor (that tested good), cleaned the TB and adjusted the throttle cable.

I was searching everywhere for answers to this problem and i read somwhere to disconnect the speedo cable and take it for a drive and that worked the car drove perfectly except the speedo no longer worked and the CEL came on after a minute, Surely it cant be the speedo cable causing this problem the speedo works perfectly when connected??? Anyone had a problem like this before ??

that is odd… no idea why the speedo cable would have anything to do with the rpms…

if that solved the issue when you unplugged it, try getting a new one and see if that fixes it…

is your throttle sticking? maybe the throttle cable getting stuck? I had that issue on my old prelude

No speedo = no VSS.

Any codes current or stored, check even if there is no CEL. 94

Nah the throttle isn’t sticking, Theres no codes but i havent been driving the car i will check this weekend though. I suspect the tps is in need of adjusting.

Didn’t end up checking codes but i unplugged the TPS and went for a drive and the car drove perfect could this possibly be the problem ?