fuel pressure regulator?

[12340987]

I have a 98 t509 and the FPR vac line isn't hooked up. Which thingie on the airbox does it go to? I assumed its the one on the right. Whoever messed with this bike before me had the airbox drain plugged up and the IACV fitting on the airbox wide open so it idles at 1500 Makes me wonder where the hose from the IACV is going...

[DEcosse]

IACV hose disconnected from airbox will make no difference to idle speed - although it definitely should be connected so it is pulling 'clean' air
FPR hose is a not a 'vacuum' line per se - again, will make no performance difference whether connected or not (after 02 the FPR was not connected to anything at all)

[12340987]

But 2000 cold idle and 1500 hot idle can't be normal. The bike is really noisy and I was hoping the IACV and FPR would help lower the idle and make the neighbors less angry.

[DEcosse]

Originally Posted by 12340987

But 2000 cold idle and 1500 hot idle can't be normal. ...

It's not!! - but not because the intake hose to IACV is disconnected
Typical leaks are cracked hoses and the TB gasket itself on the pre-02 models