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Toyota Service
Toyota Service, Toyota Expert
Category: Toyota
Satisfied Customers: 4538
Experience:  30+ Yrs of auto experience, Award Winning Svc. Manager; Just Answer Customer's Choice Award Winner
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Po442 and456 pending. Already replaced canister and gas cap.

Customer Question

po442 and456 pending. Already replaced canister and gas cap.
JA: How has your mileage been lately? Has the car been starting normally?
Customer: Have not noticed any difference,but I do not always check.
JA: What is the model/year of your Toyota?
Customer: 2004 Rav4 AWD
JA: Are you hoping to fix this yourself? What have you tried so far?
Customer: replaced canister and gas cap.
JA: Anything else you think the mechanic should know?
Customer: smell gas on occasion
JA: OK. Got it. I'm sending you to a secure page on JustAnswer so you can place the $5 fully-refundable deposit now. While you're filling out that form, I'll tell the Toyota Mechanic about your situation and then connect you two.
Submitted: 4 months ago.
Category: Toyota
Expert:  Toyota Service replied 4 months ago.

Hello. Welcome to Just Answer. Please allow me to assist you. A P0442 coupled with a P0456 indicates a small leak in the evaporative emission system. This is usually caused bey a poor connection at one of the vacuum lines at the vacuum switching valve (poor fit/cracked, dry rotted, etc) under the vehicle at the rear by the fuel tank. It also my be a crack on the vacuum port on the vacuum switching valve. I would be looking for loose vacuum connections before replacing any more parts. I am assuming that your new replacement parts are genuine Toyota factory replacement parts. Note that non=Toyota gas caps will allow this code to appear, and non-Toyota caps do not seal the system properly.