Poor fuel economy

TOYOTA SIENNA

TIMOTHY ELEY

MEMBER
1 POST

I have a 2001 Sienna XLE, V-6, 3.0 l with 90K miles. Recently, the "check engine light" came on and a P-420 code was recorded. The dealer suggested replacement of the computer. He said until the computer is replaced, the gas mile will go down, which it did. Last week, the computer was replaced and on the first tank of gas, the fuel economy does not seem to be any better than before the computer replacement. Any suggestions?

Jul 30, 2007 at 1:20 PM

RASMATAZ

✓ASE Certified Mechanic
75,992 POSTS

[quote:edf926c53a="Timothy Eley"]I have a 2001 Sienna XLE, V-6, 3.0 l with 90K miles. Recently, the "check engine light" came on and a P-420 code was recorded. The dealer suggested replacement of the computer. He said until the computer is replaced, the gas mile will go down, which it did. Last week, the computer was replaced and on the first tank of gas, the fuel economy does not seem to be any better than before the computer replacement. Any suggestions?[/quote:edf926c53a]

Sir
P0420....Catalyst System Efficiency Below Threshold (Bank 1) which normally points to an inoperatve catalytic converter not doing its job-

The oxygen sensors up/down stream has a major role in the efficienciy of the catalytic converter.

When was it last major tune-up?

Aug 11, 2007 at 5:19 PM

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