P0420 = Catalyst System Efficiency Below ThresholdCatalyst System Efficiency Below Threshold. This means that the secondary O2 sensor detects that the catalytic converter isn't working as efficiently as it should. This engine code can be triggered by any one of the following:
1.) The catalyst in the catalytic converter is cracked, clogged, or otherwise damaged.
2.) The secondary O2 sensor is malfunctioning.
3.) There is an exhaust leak.
4.) The computer unit is faulty
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It depends on how hard the pull is. It would be safest to get your vehicle fixed before getting on the highway.
If a tank has to get from a to b and there is no transporter for it, the public highway is a means of getting there without doing damage to off-road services.
im getting 17 on the highway on mine
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I have been getting about 34 highway miles and 27 city. Huge difference from the envoy I owned.
no u can not no u can not
For the 2005 LX model we're getting about 14 MPG (60% city, 40% highway) and 18 MPG (80% highway, 20% city).
Start with replacing the fuel filter, it may be plugged.
I am consistantly getting 25 MPG, Half Highway, Half City!!!
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I'm getting 11 mpg highway with the airconditioner on