rpm shoots up when clutch is pressed

[90dsm_dave97]

Hey guys im brand new to the community and have read a bunch of threads as a guest that have helped me in fixing my car but this is a weird issue for me. I have read other posts about problems similar to mine and have tried using their suggestions but no luck. First off ill list my car and mods:
1990 eclipse gsx
2g maf (wired correctly)
Big 16g turbo on 12psi
Upgraded manifold not sure on type
Ngk wires and plugs
Autozone boost gauge
Fuel pump rewired

So anyways my problem started about 2 months ago i was driving it around the neighborhood cause its not registered yet and everytime i press the clutch the rpms will shoot up. Happens at all speeds in all gears except when i take it to redline it runs normal(side note its my first awd turbo vehicle are you supposed to granny shift or should you be able to quick shift?) When i come to a complete stop the rpm will stay at abiut 3k sometimes it will drop to idle other times it will not. I have checked the ohms on the tps and they are reading normal. No boost or vac leaks. everything was fine before this bs

 

[Bojangles465]

hmm im curious, i have the same mods and same year except mine is a fwd, my car does the same thing, i wonder what this is...

 

[OakStreetTuner]

Have you performed a boost leak test? Checked base idle and timing?

 

[pauleyman]

This sounds lime a stuck throttle cable or throttle plate. Take a look at those items. Cable could be sticky. Wot you would wind the throttle spring up more which may be why it doesnt do it at wot. Easy five min check.

 

[90dsm_dave97]

Have checked for boost leak and nothing leaning towards the throttle plate or thw whole throttle body in general. I can feel tension right before it shuts all the way, like its getting snagged or something, but there is nothing i can see to stop it.

 

[pauleyman]

Test the throttle and the cable independently. Just slack the cable and work the theottle plate by hand. Does it shut quickly and smoothly? Then move the cable back and forth. Do you feel any snags? Five min and you can rule those out.

 

[BoosterJ]

I have the same problem and found it was a vac leak, you should double check n make sure that when you were hammerin your car something could've slipped out. But if you feel tension is definitely could be a throttle cable .

 

[Pale Horse]

If you passed a boost leak test then there is one more place you can check for a vacuum leak, and that is your idle air control valve. I've seen a lot of these high RPM threads tonight and for some reason the IAC is rarely mentioned. It plays a HUGE role in maintaining idle RPM. Regardless of if you're moving or not, when you press your clutch in, you're entering an idle state and if the IAC is stuck open it's inducing a huge vacuum leak, causing your RPM to elevate.