Just like everyone else seems to be having this problem, I've had problems with the EF 's idle being very rough. It's very noticeable in second gear coz it feels like it surges or as if it is missing. Its had the head gasket replaced, the head shaved, new spark plugs, new leads, new fuel filter and new injectors ( most needed replacing anyway). The car has done about 218,000kms.
Looking at other topics it looks like it might come down to doing a port and polish for the cylinders. Does anyone know a cost estimate for this?

Mate remove the crank angle sensor off the timing cover and remove the soot that accumulates there.

this will fix it.

how the hell will a port and polish fix an idle problem,,idle problems are either electrical or mechanical,porting will increase air flow sure but won't fix a bad idle.

mate seriously its best to look at all the simple things in a caselike this first rather than major issues like checking for vacuum leaks especially the map sensor or check to make sure the throttle body and idle speed controller is clean you also could have a fuel pump issue its hard to say and for a good port and polish depending on how far you wanted to go you can pay anywhere from about 500 - 2000

clean the idle solenoid on the throttle body