2009 Ford Escape Hybrid Sluggish Acceleration on Hot Days

Maintenance/Repairs
1

Y’all were really helpful with diagnosing my Fusion’s AC compressor problem, so maybe you can give me some pointers with an issue I’m having with my Escape.

Some background:

  • 2009 Ford Escape 4WD 4 Cylinders 3 2.5L MFI Hybrid DOHC
  • ~100k miles

BLUF: Sluggish acceleration on hot days

In the electrical power system menu, the battery always shows between 40-60% capacity. On hot days, it has really sluggish acceleration from a full stop or a slow roll right after starting the engine. This lasts for about 5 or 10 minutes, sometimes longer depending on how hot it is. Also, during this time of sluggish acceleration, the car won’t switch to electric at stop lights or low speed and the “Charge / Assist” indicator on the instrument panel doesn’t move.

Two questions:

Could the car be dangerous or unreliable to drive with an issue like this, especially over long distances?

Where can I start troubleshooting? I’ve heard the battery cooling system could cause this.

2

Did you ever find out anything about this problem? I have a very similar problem. Problem is intermittent and seems to go away after the car has been driven for 5 or 10 minutes. Problem also seems to be worse when the vehicle has not been driven for a few days.

3

I solved a sluggish acceleration problem with my 2011 MKZ hybrid a couple of years ago by resetting the ‘birth date’ of the battery, Ford cut back on hybrid battery use after 7-8 years for some reason, resetting the battery’s age eliminated that problem. I recently got an offer for the dealer to reprogram the car to achieve this.