St215 3sgte into St185 help

[WRX_eater]

Hi everyone,

Need some assistance if possible. I have put in the engine from a St215 3sgte into my St185 and its all working and almost everything is connected up.... What happens is the motor will run for about 1 min and then the idle will drop until it just cuts out and I think it has to do with these two lines not connected.



Can anyone advise if this would be the problem and if so how to fix it ?

Thnx

[MWP]

The large one is for the idle air control valve. It should be connected to somewhere between your air filter and turbo intake.
It wont be causing your problem though

Dunno about the small one. Where does the other end go?

[WRX_eater]

Both go to the intake manifold.

Would you have any idea why my car may be doing this? Turbo isnt connected, neither are those two vac lines

[jonathan yee]

Being that its map sensored not afm, having the odd vac line disconnected will norm mean that itll idle high not drop out. Block off the small one and see if it makes a diff, as mwp said the big one is for the iscv which if you block off it will stall most likely.