Mechanics

POOR FUEL ECONOMY

2002 Pontiac Bonneville

Engine Performance problem
2002 Pontiac Bonneville 6 cyl Front Wheel Drive Automatic 135, 00 miles

The cars runs well but the fuel economy has dropped 100 miles per tank. I changed the fuel filter, PCV valve, plugs (very clean old ones). I suspect the heated oxygen sensor. How do I change it? Also, does this model have one or two of them?
Thanks you
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Wbullock
April 23, 2008.



No that wouldnt be the cause.

Check your air filter.

And get a bottle of chevron techron, fuel system cleaner, works wonders!

Do you have white or black smoke coming out of the exhust? Is your check engine light on?

Tiny
Susman28888
May 1, 2008.