Q: code p0446

asked by on October 16, 2016

I didn't notice I park the truck on a small hill at my inlaws. The rear passenger side was the only side up on the hill. I left it running for about 3 minutes. Came out down his drive way to the next downward hill going towards the highway. I wait for traffic to pass by for about a minute or two. Gave it gas and bam, check engine light came on. Took it to O'reilly to read the code, P0446. It sounds a little bit louder then before and that's from both the inside and outside. My question to you is how concerned should I be to get this problem fix? Will it mess my engine up to no return? Should I stop driving it? For a 1998 4Runner she still sounded good until this happened today. :(

My car has 206000 miles.
My car has an automatic transmission.

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Hi there. A P0446 (evaporative emissions system gross leak detected-Toyota defined meaning) sets when there is a fault detected in the evaporative system. The evaporative system is an emissions system responsible for preventing the leakage of fuel vapor into the atmosphere. This will not damage the engine. However, this will fail an emissions test if required in your area. There are several possibilities as to what set the code, but I would take a look at the gas cap and see if it was loose or if it doesn’t seem to tighten correctly; it should have a nice clean click sound, not a crunch. Other possible faults will require a diagnostic tester and equipment to properly check the evaporative system for operation and leaks. YourMechanic has several available technicians to assist you with a check engine light inspection and provide an estimate and proper direction for repair.

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