Howdy folks new user here and I am running into a P0305 error on a 2006 4.2 Trailblazer and yes I searched the forums.
So here is the issue she starts right up, so it's not the fuel pump (which may be starting to go bad but it doesn't seem like it). The engine isn't running rough, I mean it sounds off but it doesn't sound rough.
Gas mileage isn't that bad it's getting about 14mpg, it starts right up when I crank it. Spark plugs have been changed, as well as the coil, their is no burning oil so I don't think it's a blown gasket nor do I think it's a bad valve seal. The spark plug has no signs of burning oil on it.
The FT(LT) seem a little high when it starts up but settles down after it warms up the FT(ST) seems within specs. Last time I checked the F/A ratio was about 14.9:1 so not to bad.
It fails a smog test from my ODB2 Scanner.
I am starting to lean to the 02 Sensor(s) are bad as it seems like they are the original sensors. Any other ideas?
So here is the issue she starts right up, so it's not the fuel pump (which may be starting to go bad but it doesn't seem like it). The engine isn't running rough, I mean it sounds off but it doesn't sound rough.
Gas mileage isn't that bad it's getting about 14mpg, it starts right up when I crank it. Spark plugs have been changed, as well as the coil, their is no burning oil so I don't think it's a blown gasket nor do I think it's a bad valve seal. The spark plug has no signs of burning oil on it.
The FT(LT) seem a little high when it starts up but settles down after it warms up the FT(ST) seems within specs. Last time I checked the F/A ratio was about 14.9:1 so not to bad.
It fails a smog test from my ODB2 Scanner.
I am starting to lean to the 02 Sensor(s) are bad as it seems like they are the original sensors. Any other ideas?
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