It breaks the vacuum in the intake manifold which lets the engine die down to a respectable idle.
"Where is the heater controll valve on a 2001 Chevy S-10 controll Valve? "
No.
No, it does not.
what is the valve settings surposed to be for a 87 s10 chevy pickup 2.8 ci
2003 4.3's do not have an egr valve.
There is no EGR valve on the 2002 4.3L (code W)
You can tell a bad valve by doing a compression test.
There is none.
how to adjust vavles on 2.2 1998 s10
Horn valve? Please give more info.
If you have such a valve, it was installed as an aftermarket modification. Check with whoever installed it.
If that S10 has the 2.2 L engine, it doesn't have a serviceable PCV valve.