2006 Escape Hybrid AWD just over 100'000 miles.
I use my escape for work mainly in town stop and go traffic. Today I noticed that it would not go in to battery only mode, in the past I could remedy that by stepping on the gas pedal and do short high rev runs for a bit. Today nothing, the regular engine just kept running. Then at one point it started to feel funny when putting in gear and driving away, and it got worse were it actually clunked and stuttered for a bit before taking off. Backing up a hill the engine would rev way higher then normal and barely move the car. At one point there was a funny squealing sound from the back of the car as if a brake was stuck on but it wasn't the brake as it did not stop when not moving. It lasted about 20 seconds.
I shut her down at one point for about 30 minutes after that it didn't clunk anymore when putting in gear but the engine seemed to be lacking power and was delayed to kick in. Going across an intersection was a gamble as you would slowly proceed half way before the car would speed up and go.

I had the rear differential rebuilt a few thousand miles ago. i the same time i changed all the fluids, transmission, transfer-case with the recommended Ford fluids.
Recently i had an engine code 0128 which asks for a new Thermostat but I haven't changed that yet. I cleared the code and it has not returned in 2 weeks.
The battery cooling pump was changed on the recall about a year ago.

Any ideas what I should be looking at? What could cause the car to act like this?

 

I don't know from first hand experience but could this be a sign of a transfer case going out?

 

This morning driving to work it all felt normal again, we'll see how the day progresses.

 

so far all is well but still would like to know what i should maybe check and replace to prevent this from happening again. Nobody had anything like this before?

 

Well today for the first 2 hours of work it behaved exceptionally well. Went in and out of Electric mode without a problem. Than as the battery level on the display went to almost no charge the ICE kicked in and didn't shut off anymore for the next 2 hours. I turned the car off a few times but on restart the ICE always kept running even if the display said idle and didn't show anything running. No slipping today.

 

Strange. I'm still new with hybrids but I will ask a few questions that probably wouldn't actually cause this problem but they are two things my MMH had issues with. Is the AC system working properly? How old is 12 volt battery? I'm surprised someone here hasn't offered any thing yet.

 

12 v battery was changed last year. AC system i need to check because i did turn it on today and didn't really get any cold air.

 

I think this is a very important observation. The reverse in the FEH is 100% electric, with no power directly from the engine. So if it behaves noticeably worse in reverse, that's a strong clue that the hybrid electric system is misbehaving.

 

Fascinating, I had no idea reverse was all electric. Good to know. I plan on buying a Scangage II soon. With it the SOC, HVTB temp and many other things can be kept up with.

 

got around to change that thermostat. What a pain in the .....!! i think i cursed Mr> Ford a view times. But got it done.
Now does somebody have the instructions on how to properly change the coolant for the High voltage battery?
And is it ok if I put Prestone 50/50 premix in there? the yellow kind.

Also looking for a scangauge.