sorry, I forgot they don't have a DIC. Well go fill your tank and do nothing but 55mph highway driving. As soon as you are done go fill up again and calculate your fuel usage.

should i run it like you said, 55 MPH for 10 miles and do that calculation, cuase i just filled up with 11 gallons for 184 miles?

and thats all highway?

I'd get a new o2 in there.

its not 55 constantly, its a 40 miles round trip at ~50

would my ac delco o2 go out at 30k miles?

you only have 30k on your car?

yea check da sig!

I was getting about 16 or so average, and 20 hwy. I changed my O2 and now I get a bit over 18 average and 24+ hwy. Still not where I want it, but better. O2 sensor Going out at 30K Possible. Have you considered winter blend gas, do you have to run that darn 10% ethanal blend? These things effect millage.

i dont know what i'm running right now, never looked to see the blend :(

you don't know what octane you are putting in?

ohhh...89 (Duh) dont have money for the higher up stuff