Hey I have a 1998 Jeep Cherokee; I recently took it to the shop because the check engine light came on so I had them run the car thru the OBD II System. I got three error codes P0138, P0463, P0720. They’re telling me not to worry. Can you tell me the corrective measures to take with these trouble codes. My car is not running right and I know that there is some problem. Please HELP!

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1998 Jeep Cheorkee 6 cyl

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