Question

2001 Honda Odyssey 2.3L EX with error codes P1259 and P0420 what are the possible causes? What does it indicate is at fault?

Answer 1

P1259 HONDA - VTEC System Malfunction

For the proble yo could start by checking the oil level and condition.

More information: https://www.autocodes.com/p1259_honda.html

P0420 HONDA - Catalyst System Efficiency Below Threshold Bank 1

For this problem you may need a catalytic converter.

More information: https://www.autocodes.com/p0420_honda.html