It is passible that the egr needs cleaning only. TAke it off and clean the carbon from it and where it mounts. Check the wiring and vacuum to it also. If it still doesn't work, replace it. It is the 3 inch round thing at the rear of the engine.
in what location can I find the pcv valve on my 2002 chevy tahoe
where is the PCV valve located on a 2004 chevy tahoe
Just pull it out of the hose and install the new one.
Chevy tahoe has a oriface tube
You need to CHECK the EGR Valve.
Drivers side valve cover towards the rear.
It is in a hose that is stuck in the top of the drivers side valve cover.
What year? usually in the valuve cover.
Get valve,clean it or replace it
98 chevy lddle control valve
There is no adjustment- the engine has hydraulic valve lifters.
Just behind the throttlebody. on the top of the intake manifold.