http://pdftown.com/2000-2002-Toyota-Echo-Service-Manual.html
Stick your head under the dash and look up, sort of near where the driver's left knee would normally be.
For my 2002 Echo it is 3.7 Liters with a filter change.
3.6 liters
To flush the coolant in a 2002 Toyota Echo you will need to drain it first. Flush with fresh water and then refill with coolant and distilled water.
It's electronic.
i have a 2001 and it gets about 39-42 mpg
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See related link.
The fuel vent pipe on a 2002 Toyota Echo is typically located near the fuel tank, running alongside the fuel filler neck. It connects the fuel tank to the evaporative emissions system, allowing fuel vapors to safely vent. For precise location and access details, it's advisable to consult the vehicle's service manual or a repair guide.
It is conveniently located inside the fuel tank :)
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