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In the gas tank. I have 2001 Echo.
Remove the immobilizer unit?
2001 Toyota Echo doesn't have a timing belt.
http://www.carspace.com/guides/Toyota-Echo-How-to-change-oil
http://pdftown.com/2000-2002-Toyota-Echo-Service-Manual.html
Yes
Look in the trunk, there is cover for the brake light, remove and you will have access to change the bulb.
3.5 Liters
timing chain.
see link
32 PSI