Q: Codes P0420 and P0171 appearing

asked by on June 15, 2016

I took my car to the dealership to have it checked out. Two codes were found: PO420 and PO171. They told me that the P0420 is a problem with the actuator (part number 17230-21010), and the 2nd one has to do with the Mass Air Flow (22204-21010). Both of these makes my check engine light continually appear and they told me those codes are the reasons that my gas mileage becomes so low (33 mpg on average). The dealer suggested both be replaced. But then, when I brought the car back, the check engine light went “off.”

I also have a problem with the A/C: sometimes it cools and sometimes it doesn’t. The fan is on, but not the A/C. The mechanic says there’s no code for that and they say it’s the compressor (part number 88310-47030-84) and the Expansion Valve (88515-47020). They want to replace those too. Is there anyway I can get these type of problems repaired/replaced by some place other than the dealership or are these problems ‘only’ solvable by the Toyota dealership?"

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When it relates to the air conditioning system, the dealership does not have an advantage when it comes to hybrid air conditioning systems. These air conditioning systems require special evacuation machines that are different from that of a normal air conditioning system to remove the refrigerant from the system. Due to the high cost and low use of such a machine, most independent repair shops and mechanics do not have such tools to do such services. If you know someone who does have one of these machines and is willing to help you, you are certainly able to go that route unless for any reason it would void a warranty you may have on the vehicle.

As for the Check Engine Light codes, this sort of thing can be looked at and repaired almost anywhere. You do not have to go to the dealership for this. YourMechanic offers mobile mechanics who can inspect your car and thoroughly diagnose your Check Engine Lights, as well as any other issues your car is having, so that the correct repairs can be made.

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