Q: Check Engine Light on and off, reader gives P0446 error 1999 Toyota Corolla

asked by on March 06, 2017

Two days ago, my check engine light came on and stayed on for about a day and a half. I was able to get a read on it and it came up with P0446: recommended replacement of the Engine Control Computer. Later that day, the light turned off. What should I expect in regards to cost and the level of importance on replacing?

My car has 137000 miles.
My car has an automatic transmission.

Electrical components are not working Inspection $79.99 - $99.99 Get a Quote

Hello - the P0446 code is an indication that the evaporative emissions purge valve electrical circuit has had a loss of electrical power to the vent valve that allows fresh air to enter the evap cannister. This could be a wiring problem to that valve, or a problem with the purge valve itself. It is unlikely that the engine computer needs to be replaced for this problem. I recommend a evap purge valve inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, confirm this diagnosis, and give you an accurate assessment of damage and cost estimate for repairs.

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