[DrKlahn]

Just wondering if anyone else has experienced anything like this. This morning I went to the station around the corner and filled up. It's a busy station and I see a fair amount of traffic from I-35 hitting the diesel pump. I've filled up here before with no problems. So I put in my fuel treatment and topped off the tank just like normal (no overfill just let it click off). There was no wind to speak of this morning. Temp around 30* F. I took the same route I always do into work. I always leave the display on the ECO setting with the instant economy on it. Cruise control set at 60 mph. I noticed that on the flat areas I am averaging 32-34 mpg. I usually get upper 40's to mid 50's in these areas (as it has gotten warmer it has been getting even better). I mute the radio to make sure I haven't ran into a crazy head wind. Nope. So that goes on for most of my trip into work and my average is just tanking. In the last 5 miles it all of sudden picks up to the normal numbers and the average steadily climbs back up (total trip is 30 miles).

The car ran smooth. No idiot lights. So now I'm left wondering what is going on. Would diesel in the tanks at the station settle to the point of something in there causing this? I know the car will dump fuel into the exhaust to clean the filters, would it have that sort of effect? Could mixing diesel from 2 different stations cause the ECM to do something odd with fueling? Just really weird that it would be so drastically under where it usually is for 25 miles and then for no apparent reason bounce back to normal.

 

[Danny5]

Regen

 

[vwgtiglx]

Regen

I concur.

 

[DrKlahn]

Thanks for the replies. I just love coincidences. Fill up the tank and it decides to do something different at the same time.

 

[mcbockalds]

I guess one might also wonder about the accuracy of the computer calculating the MPG?

 

[obermd]

I guess one might also wonder about the accuracy of the computer calculating the MPG?

The gas Cruze has an optimistic calculation. Most of the CDT drivers have reported very accurate computations.

 

[boraz]

yeah regen

 

[revjpeterson]

The gas Cruze has an optimistic calculation. Most of the CDT drivers have reported very accurate computations.

Some of us are also seeing pretty pessimistic numbers from the DIC. Mine is consistently 5-7% pessimistic.

I know the car will dump fuel into the exhaust to clean the filters, would it have that sort of effect?

That's the regen, and the behavior you mention is textbook regen behavior for the car.

 

[VtTD]

The gas Cruze has an optimistic calculation. Most of the CDT drivers have reported very accurate computations.

Mine is right around 2 mpg pessimistic. Almost every time. Drive style does not seem to matter.

 

[WI Diesel]

Mine is also consistently 2 mpg pessimistic every fillup.