Chevrolet Repair: oxygen sensor, chevy cavalier, fuel burns

Question
QUESTION: i am looking to find where the front oxygen sensor is on a 99 chevy cavalier 2.2L

ANSWER: Hi,

 The 2.2l upstream sensor is in the exhaust manifold and has a 7/8" hex fitting.

Wayne


---------- FOLLOW-UP ----------

QUESTION: my gas gauge goes down fast for the first 1/4 of a tank. can this be due to the oxygen sensor or is there something else going on.

Answer
A fuel tank is not perfectly square and the time it takes for fuel to drop should have no relation on fuel level.  The only way you can verify this is to calculate distance vs volume of fuel.  As fuel burns at different levels of the tank the area of the fluid will change and the gauge will drop at different rates.  It might not be bad on fuel.  Fill the tank and mark the kilometers.  Drive a full tank and fill it up and mark the kilometers again. Divide and figure your mpg.

wayne