Check the codes. And do like patriot07 said. go from there.But warning...on gm vehicles sometimes when you unplug the throttle body it will need to be re calibrated and when you crank it up it will want to run wide open. You can remove the the throttle body from the intake and clean it with out unplugging the wire harnesses from it.Yea its a *#*## but it can be done. I recommend Berymanns.
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