Near-death O2 sensor, what effect would it have on MPG?

[55Test]

Found out today that my O2 sensor on my Ciera is on the way out, the wires are corroded and falling apart or something. I assume this is what's causing my SES (service engine soon) light to turn itself on an off at differing times. How much of an effect on fuel economy would an essentially non-functioning O2 sensor have? I notice my fuel mileage isn't what I expected it to be, I put $54 in the tank, at 88.9 cents per liter that's just over 60 liters, or 15.8 gallons to you US folks. I only managed to get just over 400 kilometers, 249 miles, to the tank before I decided to refuel. My fuel gauge becomes wildly inaccurate at about the 1/4 tank mark, so who knows, I may have been able to go further on that tank of fuel. Does that sound low to you?

 

[rpn453]

400km on 60L? Got a 454 in that thing?

 

[pitzel]

I was only getting 500km with a full tank of fuel driving on the highway at 100km/hr with my 1992 3.1L V6-powered Oldsmobile before I replaced its oxygen sensor. I had just acquired/inherited the car and was pretty disgusted with its fuel efficiency.

In went the new Bosch from Crappy Tyre, and I was able to make it to Calgary from here, a 700km run, on a single tank of fuel before the low fuel light came on. Also switched to Mobil-1 5W-30 at the same time from Wal-Mart installed 10W-30 Pennzoil dino. All in the spring, so weather wasn't a huge factor here.

Thats what, a 40% gain? O2 sensor paid for itself just in fuel savings in a quick roundtrip to Calgary and back.

ps. rpn453: do i know you from somewhere? your nickname sounds awfully familiar ;-)

[ February 08, 2005, 08:55 PM: Message edited by: pitzel ]

 

[rpn453]

quote:

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Originally posted by pitzel:
rpn453: do i know you from somewhere? your nickname sounds awfully familiar ;-)

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Oh no! Someone has discovered my lack of creativity!