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po400

  1. PO172, PO400---Garage says I need a new throttle body

    OEM Issues
    So the Envoy is begging for me to replace it, but I'm too stubborn because I love it. Last Friday on my drive from VA to PA (300miles) it wasn't running the greatest. Over the weekend the SES came on with a PO172 and PO400 code. I didn't have to go anywhere so I wasn't too worried. Monday comes...
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