It's the wife's car, and I rarely drive it, but I noticed on a previous drive that the average had dropped from the low 30s to the high 20s and assumed it was due to the cold weather.

However, the next time I drove it the MPG had dropped even more to 27.x, which is when I also saw the wrench light. Once I replaced the actuator the MPG shot back up to the low 30s and has stayed there for over a month now. Roughly the same weather conditions too so figure it had to be the actuator replacement that corrected it.

 

Wow. Good to know.

I always got an MPG of 28-30, but in the past several months its been about 26, all based on the Gas Cubby iPhone app.

In that time I've bought new tires, replaced the MECs pump and moved from MD to TX where my weekly commute is almost 175 miles less. I figured between the tires, roads, possibly different fuel mix and a 6 mile drive to work with heavy AC use, I was getting a drop.

I ordered the actuator from Ford Parts Giant. So hopefully I can tackle that installation (it doesn't look any worse than replacing 4 speakers and the OEM stereo) and get rid of the wrench light and reclaim a few MPG.

Thanks!
-t.

 

Actually, that short commute is most likely the culprit.

 

My blend door light came On for 40,000 miles till I sold my '05. It never affected my MPG at all. The shorter commute, coolant pump, and the new tires are most likely the cause of the lower MPG.

GaryG

 

I'm now at 151,000 miles. As far as I know my 8 year old blend door is still working.

What I have always thought was really dumb is.....

The battery cooling fans are variable speed. Dandy.
But they always turn slowly when in EV mode for noise abatement.
Well, in EV mode is when I use the most battery amperage and generate the most heat!
So it is a vicious cycle.

Last night it was 55 degrees outside and my battery hit 88 degrees, closed the blend door and turned on the A/C compressor.

I hate that.

I have long wanted manual control of the battery fans.

 

How would the coolant pump effect MPG? Because it's a new part that needs breaking in?

-t

 

Not at all. New parts don't need "broken in". It's because those systems support traction battery cooling, hence helping to improve MPG. Thus, their improper performance will negatively impact MPG.

 

No, when the electronics get hot, you don't go EV. This will drop your MPG because the engine is running more.

GaryG

 

That makes sense.

I had my MECS pump replaced in August in the middle of my 1500 mile move from MD to TX. I noticed the mileage drop in the months after the MECS replacement, new tires and a much shorter commute.

I should have quoted myself to be more clear. Sorry.

-t

 

I replaced the actuator today.

All in all, not too difficult, but that last screw is really tough to get to.

Hopefully that wrench light will stay off for now.

Thanks to all here for the tips and advice on this DIY repair!

-t.