Starboard Engine idle's Faster

[Fullvolley]

Looking for and ideas on where to start looking.

I have a 2003 360 Sport Sedan with 5.7 Volvos and ZF 61 transmission with 600 hours on both engines.

Issue: After the engines warm up and I run it for a little while, the Starboard engine runs between 800 and 1000 RPMs higher than the Port side when idling. Normal idle is ~800 RMP, which is where the port-side engine stays.

Since the starboard engine is at such a higher RPM, shifting is very hard. Not good!

Any suggestions would be greatly appreciated!

Thanks!
Rob

[g36]

when the idle is high i would go down to the engine and verify the throttle linkage is not binding and causing the linkage to not go back all the way i.e binding/sticking
maybe need to remove air cleaner to check it where it attaches. might totally remove it and verify the high idle condtion is still there or it goes away when disconnected. tru cleaning it.
could also be iac valve (idle air control) might try cleaning it with thottle body spray cleaner etc.
i dont have this engine but, any vacuum hoses? might have a air leak somewhere also
one more thought maybe throttle position sensor (tps sensor)