Gas Mileage Problem on '06 coupe w/22k miles

[ZO6KLR]

Seems like here recently I have ben filling up more often than I am accustomed to.
I filled up (18.5 gal), 40 bucks worth, and clicked the odometer. Most of my driving has been highway with 3 heavy acceleration blasts (2nd-4th up to 110 and yes, I kept track).

My fuel light came on at the end and I drove about three more miles to the station. Odometer read 140.6. That averages out to a whopping 7.6 mpg.

Now, if I can remember correctly, I was getting around 180 to 200 on a full tank.

Another thing I have had going on was an O2 sensor going bad. It would flash the code periodically and I would just ignore it and let the computer cycle through and finally it would reset itself. I have also been noticing that the ***** has been running very rich, almost bring a tear to my eye when I am at a light.

Would something like the sensor be the major cause of the issues I am having? I mean, I know the Viper ain't a Prius but I know it should be getting at least 10 or 11 mpg. Anyone have some insight?

 

[RTTTTed]

You changed the 02 sensors and it still gets bad mileage? Perhaps a connector problem?

Ted

 

[ZO6KLR]

I never changed the O2 sensors. The car has aftermarket exhaust with no cats.

 

[RTTTTed]

ALWAYS change the 02 sensors as soon as there's a problem. There was a lot of counterfeit or 'bad' manufactured sensors and buying Mopar parts should save you that heartache. Change the sensors.

Without Cats the ECU has a program that can add fuel to "save the Cats" from overheating and that may be what you're experiencing - wasting your fuel. That has to do with the rear 02 sensor system. The rear sensor system can be turned off with a SCT tuner and may be worth the cost to prevent tuning issues and other problems.

Ted

 

[ViperGTS]

>>>2nd-4th up to 110 and yes, I kept track<<<

Do you use 5th and 6th gear at all ?

 

[Malu59RT]

Wow, I've gotten 300+ on one tank, and as high as 25mpg. Never have I been able to put more than 15 gallons in the Viper, and I have to ride it way past the "E" to get 300 miles on that tank.

 

[dragon rider]

Yeah that is low. I to normally get 200 miles between filling up. Sounds like your sensors need replaced.

 

[cash84]

I have no cats in my 06 and that kind of milage you have is what I probably get in the city. Highway i gotten up to 27 but average around 24.

I have a thought that the o2 sensors wouldn't decrease the milage that much. I have had other cars with bad o2 sensors and only knocked it down maybe 1-2mpg