Speedway fuel MPG AVG gone haywire!!!!!!!

[apopilot77]

I had to fill up fuel and stopped by a local Speedway. I normally fill up at a Mobil, Amoco, or Shell. After I filled up on standard octane 87 fuel I started the vehicle and noticed my MPG AVG jumped by 10 then it started oscillating up and down. Has anyone ever experianced this before? Any ideas?

[apopilot77]

Anyone?

[DaveM]

I've only had my FFH for a couple months and have only had to fill it twice so not that in tune with the avg. mile per gal but on our Caddy STS when you reset the average it goes to zero until you pull away and then the average is all over the ball park depending on how hard you push on the go pedal. As you get a few miles on it this slows down and the more miles on the tank full the less it moves. I think this is what you are seeing and is perfectly normal. What I don't see anymore on the hybrid is when sitting at a red light on the STS I could almost count on the average going down 2 tenths of a gal. Has yours settled down now? If so I think what I said above is what you were seeing.

[apopilot77]

I've only had my FFH for a couple months and have only had to fill it twice so not that in tune with the avg. mile per gal but on our Caddy STS when you reset the average it goes to zero until you pull away and then the average is all over the ball park depending on how hard you push on the go pedal. As you get a few miles on it this slows down and the more miles on the tank full the less it moves. I think this is what you are seeing and is perfectly normal. What I don't see anymore on the hybrid is when sitting at a red light on the STS I could almost count on the average going down 2 tenths of a gal. Has yours settled down now? If so I think what I said above is what you were seeing.

 

 

Yes it has settled down and barely moves. However, the moment I pulled out of the SPEEDWAY gas station the AVG MPG went nuts.

[DaveM]

Yes it has settled down and barely moves. However, the moment I pulled out of the SPEEDWAY gas station the AVG MPG went nuts.

Sounds like it is working as it should. It is trying to average your mpg when there isn't any miles on the new tank. I have found it takes about 60 to 80 miles before it really starts settling down and then if you floor it the mpg will drop quite fast. I don't know how many miles you have but you will notice that the long term mpg barely moves at all and the more miles you put on the car the less it will move at all. Somewhere it will get to the point where it may not get any better and you could see a slight decrease once in a while like winter time. Summer will see it raise again. Forget about it and enjoy your ride.

[apopilot77]

Sounds like it is working as it should. It is trying to average your mpg when there isn't any miles on the new tank. I have found it takes about 60 to 80 miles before it really starts settling down and then if you floor it the mpg will drop quite fast. I don't know how many miles you have but you will notice that the long term mpg barely moves at all and the more miles you put on the car the less it will move at all. Somewhere it will get to the point where it may not get any better and you could see a slight decrease once in a while like winter time. Summer will see it raise again. Forget about it and enjoy your ride.

 

 

Let me rephrase. I have had the car for 6 months and it settled down months ago. As soon as I put in the Speedway gas it started moving all over the place.

[DaveM]

Let me rephrase. I have had the car for 6 months and it settled down months ago. As soon as I put in the Speedway gas it started moving all over the place.

I guess I wouldn't buy Speedway gas then. I use it quite often but here in Mich. we can get what I call real 100% gas and I have no problems.

[Oman]

The gas can't cause this. The display is an average of past information. There have been several reports of resetting MPG numbers upon restarting the car. If this happens the reading will bounce wildly for the next hundred or so miles until it gets enough data for a more constant average.

 

Depending on the production date of your car there may be a service notice for it. Tell your dealer service center that you have been having the dash MPG numbers reset when starting the car. They can check.

 

Again, nothing to do with the gas.

 

Jon

 

 

I guess I wouldn't buy Speedway gas then. I use it quite often but here in Mich. we can get what I call real 100% gas and I have no problems.