idles good till full orp temp then surges if kick in neu it stops
have replaced idle air control sen cleaned trotle body fuel pres good 62lbs &
up left w mech he couldn't find vac leak any idea ???
My mech friend saw this problem recently and suggested you look at the throttle position sensor (TPS), you may have a dead spot or spikes in it's range of motion. Another suggestion is to replace the EGR and not with an aftermarket one, go to the dealer for it. Lastly, surging can also be a sign of a bad fuel pump or sending unit.
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