Does tuning out o2 sensors hurt mpg?

[volkswagensRus]

Car is 2001, so wide-band. Will having the tuner dial out my o2 sensors due to catless DP hurt my economy at all?

[Wrath And Tears]

The quick answer to your question: Absolutely, how can the car control it's AFR if it can't read it.

What you really mean to ask is does getting the post cat O2S coded out hurt MPG. The answer is no. The post cat O2S is used to monitor health of the cat.

Edit: Redline is probably right in that it has some effect on mpg. You will probably do more harm mpg wise simply having fun driving.

[redline380]

From what I have heard, the secondary o2 sensor does indeed contribute to fuel trims. I did not figure this out myself and it is just hearsay at this point, but it is something to consider. It contributes minimally, though.

With that said, who cares? Gas is cheap. Love it while it lasts. It is probably the cheapest we will ever see in our lifetimes.

[Davdraco1]

I have mine tuned out and I saw no change in mpg at all. Still average 23-24

[volkswagensRus]

Ah yes, I guess I meant the rear (secondary) o2, Davd. Thank you guys. Right now in the middle of winter amidst crazy blizzards and my assholish driving I'm getting 27-28.5mpg around town, no highway driving. I also have a cel for 'excessively retarded camshafts' due to a worn cam tensioner. I anticipate these mpg figures going up exponentially in the next few mos, and don't wnt the rear o2's hindering this.

[Davdraco1]

How are you getting such good MPG around town??? That's what I get on the highway....

[volkswagensRus]

I'm very very good at getting good mpg out of my vehicles. My honda gets 41-42 mpg doing the same trip in the summer time; winter it's been 33-37mpg in the Honda.

[Davdraco1]

My 98 civic cx gets 30 around town. How the hell are you getting such good mpg.

[volkswagensRus]

All depends on the drive and how one drives it. We got a series of blizzards for a week straight and driving the audi and getting sideways relatively frequently I netted 25.5 mpg... I was disappointed but it was still 10mpg better than I could get in my tahoe in similar driving/conditions. And much more fun. The average speed readout on the audi is 28 miles per hour so it's nearly all city driving that I do with it.

[Mad Cow]

From what I have heard, the secondary o2 sensor does indeed contribute to fuel trims. I did not figure this out myself and it is just hearsay at this point, but it is something to consider. It contributes minimally, though.

With that said, who cares? Gas is cheap. Love it while it lasts. It is probably the cheapest we will ever see in our lifetimes.

It's not hearsay, they'res plenty of official bosch documentation that says it does. That being said, all it does is compensate for O2 sensor aging, so if you have a fairly new sensor it probably wouldn't matter one bit. Also depending on how it's coded out it could still compensate if you keep it installed.

I wouldn't worry about it.

[volkswagensRus]

^Good info. thank you all very much.

[Wrath And Tears]

fuck it don't care

[volkswagensRus]

My last tank on my 2006 honda 5spd LX was 35.5 mpg and I was driving like a major asshole and it's been 0-20* f.