Danny,

With the O2 sensor uplugged, your van is running full rich.  Not only
is that bad for your MPG, it will also cause early failure of your
catalytic converter, and it really sucks for the environment.

Cheers,

Jeff

On Thu, Aug 13, 2009 at 2:59 PM, Danny C.<bruiserbabie@yahoo.com> wrote:
> oxygen sensor HELP.....
>
> So I have a very gone through engine rebuild (1.9L) With lots of new parts (1984 water cooled vanagon with auto trans). My mechanic tells me to leave the oxygen sensor unplugged so that the engine will run cooler. I am only getting 15 MPG and was wondering if I plug it in if I will see a difference in fuel mileage for the better. Or if having it un-plugged is bad. Please share with me the pros and cons of the oxygen sensor. Thank you.....
>
>
> Danny C.
> '84 Westy (Vanny)
>
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