EnvoyTransmission Solenoid Cost on 2008 GMC Envoy

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What should it cost to replace a Air check valve Solenoid that they are also calling a Air Solenoid Stuck. I have had 3 differant diagnosis on this trouble code with the last being it is a transmission part. I have been quoted as high as $500 from the dealer to as low as $200 from a local shop that claims it is an emissions part that should be covered by warranty. I dont know who to believe!
(1) Answer
If it's really a problem with an 'air solenoid,' then it's an emission system part and may be covered by the warrantee on the car. If so, there shouldn't be any charge to repair it. Find out if you still are under the emissions section of the warantee. You may have to pay for diagnostic time of about 1 hour which should be refunded if it's an emissions related problem and therefore covered. You may want to find an GM specialist. But remember, a GM dealer is the only place to get warrantee work done, anywhere else will have to charge you for it unless there's an arrangement between GM and the shop you choose.
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