I have a 72 240z and last week I worked detailing the engine I took all intake and exahust out as well as the carburators, clean an painted them , when I put everything back the car runs ok but when it warms up the RPMs are high arround 1800, any Ideas what could it be , or what can I do to get them lower?

Also when I shut the engiine it kind a chokes.

 

Are they the ones located on top (plastic *****) of each carb?

 

The idle screws are located near the bottom right hand side. They should have a spring shroud. The plastic ***** sound like the oil resevoir

Gotta get my Z's

 

It's prob just the idle screws needing adjustment 'cause you've cleaned out some gunk and it's now breathing better. But, just check that you've got the throttle linkage on properly. This one time when I first took the intake apart I put the linkage back on wrong and one carb was about a quarter open and the other was at idle.