Q: The check engine, Trac off and Vsc light came on my car. The code that came up is P0446 (Evap System Vent Control Fault).

asked by on November 23, 2016

I drive 2001 toyota sienna with 100,000 miles on it. The light came on after three weeks of purchasing my car. I got the code by getting it scanned by a shop. The codes have not gone away, it's been 3 months now. I tried tightening the gas cap, it didn't work. I also tried putting 93 octane gas, it didn't work. After one week of trying these steps, the lights went away for 3 days in between and came back on after the 3 days. Now it has been about 2 months since the lights have remained on.

My car has 110000 miles.
My car has an automatic transmission.

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Hi there. That light is not going away until the fault has been properly diagnosed. The code may or may not be the same. The code that is stored is a guide for a qualified technician to use. It does not offer a diagnosis, only a guide to the system with the fault. The code you mentioned, PP0446, is an evaporative emissions code when the system detects a fault during self testing. This system prevents the escape/release of fuel vapor into the atmosphere as regulated by our lawmakers. I strongly suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts. Your Mechanic has several available technicians that can assist you with a check engine light inspection.

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