CO2 recall and lost fuel milage

[RayB]

Had the co2 recall done, and my mileage went down. I was getting 20 to 21 before and know it is down to 17. 5 running empty. Any one else have this happen.

 

[Parshal]

There's been quite a bit of discussion about this on the board and there doesn't appear to be a consensus. Some people's mileage went down and some was unaffected. Mine went down. There was a thread on another board where someone said their mileage went up!



I called the service manager at my dealership and taked to him about this. He said when DC makes a flash update to fix a specific problem they usually change many other things that they do not announce. Even he doesn't know all the changes. He did say that unless mileage drops by 5 - 6 mpg DC won't even pay attention.

 

[GWDiesel]

RE co2,reprogram,

My milage dropped from around 18. 5 down to 16. 8 ands the motor unwind's very slowly when shifting up to the next gear!

I hope to be back home in CO in July and I hope I don't go to

the same dealer you called! GWD

 

[Blakers]

What is the CO2 recall all about?

 

[robobx]

I'm wondering if the flash is reprogramming the how it figures the mileage too?

 

[THanley]

CO2 Recall & Lost Mileage

I heard about this issue as well. So before I went to have it done, I monitered the mileage readings on the overhead computer. After the re-flash, it seemed that nothing had changed in my mileage on the way home.



On a day or two later, I went on a 600+ mile trip, and saw a decrease in mileage at the trip computer. Was this a real loss in mileage? Was it head winds? I don't know, because I did not verify it with the fill method.



Several thousand miles later, however, my mileage seems to be back where it was before the re-flash.



I have had some people comment that during the re-flash process, the technician did not input the correct tire size. Or the incorrect rear end ratio. This will definitally change your mileage numbers on the trip computer.



My suggestion is that if you are seeing a big drop in mileage on the trip computer. First, try and verify it with the fill method. If the computer is off, take it to the dealer and verify that they have the correct parameters set. e. g. tire size and rear end ratio.

 

[lschultz]

I had the reflash done on mine. I have not noticed any difference in performance but watching the overhead I have lost several tenths. I kept a record of mpg before reflash and after and I will go back to them and have a discussion about this. I will just have to pull out my book and show them where my mpg started dropping and this is when they did the reflash. Its possible they did not put something in right but the ole boy that works on them is good. They did something cause my driving style has not changed. All my mpg have been 19+ since then. I was hitting 20+ occasionally.

 

[Fireman]

All I can tell you guys is that the mileage on the overhead computer did drop a couple of mpg, BUT the actual mileage ( figured with a calculator-miles/gals. ) has remained the same. My computer always showed 1-2 mpg more than actual. The upside is that now my computer mileage is within a couple of tenths of the actual milage.



Fireman

 

[Blakers]

What was this recall all about? What were they trying to correct? Is this a problem only on the early 03s?



Thanks

 

[Casey Balvert]

The CO2 recall corrected a high idle condition that occurred after prolonged engagement of the cruise control. I involved trucks built fairly early in the model year. My mileage has not changed and the computer was accurate both before and after the reflash was completed.



Casey

 

[Blakers]

Ok Casey, thanks for answering that for me. I heard about that recall, but was in the dark as to why it was called a C02 recall. My truck was born in January and doesn't have that problem.



Take it easy.