ECO mode

[The Waco Kid]

I understand having to have a light food to engage Eco mode. What I don't understand is why it isn't coming on as much lately with temps a little cooler. I live in Houston. Most highways are flat as a pancake.

Just a shot in the dark here....maybe because a warmer ambient air temperature aids in creating a better fuel vapor mist out of the injectors (flash point/vapor point), causing a better flash after spark, causing a more complete combustion, and less fuel consumption..... all vs cold temps, which is the opposite. Cold climate mpg's & performance have & will always suck vs warm climate, IMO.

 

[snj1013]

Just a shot in the dark here....maybe because a warmer ambient air temperature aids in creating a better fuel vapor mist out of the injectors (flash point/vapor point), causing a better flash after spark, causing a more complete combustion, and less fuel consumption..... all vs cold temps, which is the opposite. Cold climate mpg's & performance have & will always suck vs warm climate, IMO.

Not sure. I'm not talking cold ambients either. Talking ambients in the 60s vs 80s and I notice the truck not going into Eco mode on the highway as much.

 

[snj1013]

So it's still coming on, but not as often. I can only guess it has to do with the outside parameters that triggers engagement. Also, when is the last time you got an oil change? The system is dependent on the oil viscosity.

My truck only has 3500 miles on it. Haven't changed the oil yet but might do the first one next week.

 

[TX_Phil]

I understand having to have a light food to engage Eco mode. What I don't understand is why it isn't coming on as much lately with temps a little cooler. I live in Houston. Most highways are flat as a pancake.

I drive from Sugarland to Tomball or to IAH almost daily and I've found that wind and even the road surface makes a difference. Hwy 99 from I-10 to 290, almost never get ECO mode at 70 mph but on 290 from Hwy 6 to Hwy 99 I can run 80 in ECO mode. Same time of day, same temps, no wind, only reason I can come up with is the roughness of the road surface.

To your point though about suddenly not finding ECO as much as a few weeks ago, I've noticed the same but thought it was just traffic. I know on my motorcycle I see a MPG drop when the change the fuel formulation (summer vs winter gas). I wonder if that has any impact on ECO mode?

 

[slimchance]

it was 30 degrees the other day and my ECO light was on most of my trip .... don't think it is temp related based on my trk and the wife's trk

 

[Konrad]

All the ECO, MDS etc. modes are tightly related to calculated engine load, which in turn is dependent on ambient air temperature and atmospheric pressure.

By SAE J1979:

LOAD_PCT = [current airflow] / [(peak airflow at WOT@STP as a function of rpm) * (BARO/29.92) * SQRT(298/(AAT+273))]

Where:

- STP = Standard Temperature and Pressure = 25 °C, 29.92 in Hg BARO,
- SQRT = square root
- WOT = wide open throttle
- AAT = Ambient Air Temperature (in °C)

Characteristics of LOAD_PCT are:

- Reaches 1.0 at WOT at any altitude, temperature or rpm for both naturally aspirated and boosted engines.
- Indicates percent of peak available torque.
- Linearly correlated with engine vacuum
- Often used to schedule power enrichment.
- Compression ignition engines (diesels) shall support this PID using fuel
flow in place of airflow for the above calculations.



Sent from my iPad using Tapatalk

 

[JJRamTX]

I drive from Sugarland to Tomball or to IAH almost daily and I've found that wind and even the road surface makes a difference. Hwy 99 from I-10 to 290, almost never get ECO mode at 70 mph but on 290 from Hwy 6 to Hwy 99 I can run 80 in ECO mode. Same time of day, same temps, no wind, only reason I can come up with is the roughness of the road surface.

To your point though about suddenly not finding ECO as much as a few weeks ago, I've noticed the same but thought it was just traffic. I know on my motorcycle I see a MPG drop when the change the fuel formulation (summer vs winter gas). I wonder if that has any impact on ECO mode?

I think the Summer and winter blends have a definite impact on ECO. With a fill up in Texas 2 weeks ago I was only getting 14.5 MPG and after burning through that tank and filling up in Colorado I am back to 18 MPG. It could have also been contributed by the quality of Gasoline because I got gas at a Phillips 66 and Murphy USA instead of my usual Costco.