2010 Hybrid won't shift to EV while driving and outside temperatures below mid-40s

[jzavadil]

My 2010 Hybrid has about 88K miles on it and started acting up about a month ago when outside temperatures started to drop (North Carolina). Basically, the hybrid system won't shift to EV while driving unless I have my foot on the brake pedal if the temperature is in the mid-40s or below. Acts more like an Engine Start/Stop system (does go to EV at stop lights, but as soon as I ease up on the brake pedal the engine starts). Engine runs continuously and battery stays pretty much topped off; the system is using the battery during acceleration so I don't think it is a HV battery issue. Mileage has dropped about 5 mpg as a result. Took it to the dealer who, naturally, could find nothing wrong - they tried to educate me on how the hybrid system functions, but I've been driving this car since April 2009, so I sort of have it figured out. After watching a bunch of videos, I realized that the little temperature indicator (next to the engine coolant temperature indicator) that is supposed to indicate that the system is warm enough for normal hybrid operation never changes color from white to green, even when the engine is fully warmed up. I don't know if it has ever changed color, but the owner's manual says that it should change. If outside temps are in the 50s or above, the hybrid system operates normally, even though the dash sensor remains white. So it seems like the hybrid system is not sensing engine temperature properly, but I don't understand why the outside temperature matters. Thermostat issue? Some other sensor unique to hybrid systems?

[Allamand]

That is strange, and if the light isn't turning GREEN on the temp gauge, something is wrong. Maybe reset the computer by removing the battery? 

[VonoreTn]

Perhaps the thermostat is stuck open.  If so the engine temperature will be about 160F max instead of 190F constant.  I don't even know if the FFH uses a conventional thermostat, but that happened to me several times years ago on a conventional car.  And in really cold weather, the heater would be challenged. 

[Campenella]

I live in Wisconsin, just had a similar experience, 2010 with 210,000 miles.  Took the car to the dealer, after a week there and them having discussions with "the hotline".  No codes showed up after all their testing.  They felt it was the cooler temperatures.  They also updated the modules, which I am convinced changed a few things on the car but no one seems to agree with.  Once it warms up, we will see.  The cooler temperatures do have an impact on mileage but the EV should still kick in when the engine is warmed up, at least that is how it worked in the past.  Once your temps return to normal, your mileage should.

[jzavadil]

I'm confident it is related to the temperatures. A few days after taking the car to the dealer, outside temperatures returned to the 50s and 60s, and the hybrid system returned to normal operation (although the hybrid temperature gauge is still white). The temperatures are now back in the 30s and 40s and the problem has returned. I'm going to get the car into the dealer on a cold day and see if we can figure it out.

[lolder]

The thermometer turns green when the engine temperature reaches over about 60 º C. This can be read on the Engineering Test screen. I forget how that is accessed. Maybe by pressing the right side of the bottom two buttons on the left side of the steering wheel for 5 seconds while turning car on. There are 10 screens to cycle through with one of the buttons.

Edited December 13, 2018 by lolder

[WalterTA]

jzavadil - Did you ever determine the problem?  I have the exact same issue.  The little green temperature light does come on, but the EV is only engaged when my foot is on the brake.  Thanks!

[jzavadil]

I haven't taken it back to the dealer yet...waiting for some colder weather.

[WalterTA]

On 12/15/2018 at 10:04 PM, jzavadil said:

I haven't taken it back to the dealer yet...waiting for some colder weather.

Thanks.  Please let me know what you find out.  I'm taking mine in for the airbag recall and figured I'd have them look at the hybrid system while there.  

[MikeL]

Hi,

Joined this forum for the exact same issue.  I only have 108k on my 2010 Ford Fusion Hybrid. I have  had the car for 4 years [bought it used] worked great the whole time got about 43mpg.  Now I'm only getting 27-30mpg.  Its the same thing on EV when braking as soon as I let off the brake it starts the gas motor and stays on.  Battery is registering good . EV  still works on back ups. 

 

It seems to have started when I took it to a "reputable repair show"  who claimed he knew hybrids.  How wrong was that I!  Anyway he was suppose to fix my AC he said a stone poked a whole in the evaporator and it needed to be replaced.  He charged it with Freon [ 3 times i kept bring it back] till that last time when he claimed it was a leak he couldn't see.  Lost all confidence in them.  Now I am stuck with a previously awesome car that even Ford cant figure out.  I did need a water pump which Ford did for a mere $850.00 [very costly] but that job required the axle be removed to do, don't have that kind of time or equipment in my house garage and no longer trust secondary shops.  . Ford did a nice job on the H2O pump but failed at diagnosing that EV issue.   Note though they did charge me $178.00 for an hour of diagnostics; even though they could not find any EV problems.  Personally I think its a ploy to get me to buy a new Ford, they are over run with new cars, no room to park when dropping off and picking up this Fusion.  Mind you this is a 3 acre full service ford dealer.  

Todate this is what I have done.

 

1. Cleaned my Throttle body.  [ However I notice that the "butterfly" was not completely engaged closed when removed to clean].  Called suppliers to confirm if this is an indication of a failing TB.  So far not results.

2. Reset the the Throttle body by removing battery and discharging then relearning [ did this after the car was warm tried cold first did not change things]. Car did relearn as the process states, but did not clear up issue.  

 

As an engineer I will find this problem and report back to this forum. Unfortunately my degree is in Aircraft and not auto, so it may take some time.  

[WalterTA]

Going to the dealer tomorrow.  I'll let you guys know what they tell me.

[jzavadil]

So the car has been at the dealers for the last 2 days. They agree that there is a problem. They called the Ford hotline and were told to "recondition" the battery. I don't know exactly how that works - supposedly balances cells out; but the dealer carried out the procedure but it did not fix the problem. So they gave me a loaner car (brand new Escape!) and said they were going to keep the car until they figured it out with Ford. Nothing heard today.

 

One correction to my earlier posts. The indication that engine temperature is sufficient for hybrid operations actually IS working, I didn't realize that you needed to be in Empower mode for it to work. In Empower mode, the indicator does turn green, but the hybrid system still doesn't operate properly.

 

Don't think it is the throttle body - I had mine fail and had it replaced a few years ago. Believe it is either the system thinks the engine is always cold or it thinks the battery is always low - my dashboard indications don't show either to be the case, but those indications may not be making it to the computer.

 

More to follow...

[WalterTA]

Just picked my car up from the dealer.  They purportedly ran every diagnostic in the book and told me that they cannot find a problem with the hybrid system.  Oh, well...  Will try a different dealer soon.

[jzavadil]

Mine went to the dealer on Monday. I got a call today (Thursday). Basically they contact the Ford "Hotline", Ford says "try _______", they try it, it doesn't fix the problem so they contact Ford again. Definitely giving it a good effort, and since I have a loaner car I am patient. Will let you know how it goes.

[Capt. K-9]

Anyone get the dealer to change the thermostat?

 

 I’m old school, if a VOM meter counts as a computer then I’m computer savvy.

took my fusion hybrid 011 with 160000 to those rip off part changers at Ford and no dice.  I asked about replacing the thermostat and they looked at me like is was from another planet.

 

do t want to do it myself, so I rigged a temp gauge up to check my theory...and low and behold the dam thing is running cold, at 30F degrees it reaches 180F standing still and running at ideal, but cool quickly when shifts to EV mode.  but moving it fluxuates from 160 to 180, EV kicks in normally at 180, but not so much when it cools off below 180 and my fuel eco is in the tank.. like 33mpg.   

 

Somi  I went really old school an put a sheet of cardboard in front of the radiator.  Damn thing is holding at 180+... haven’t had a chance to drive much and see if it operates normally or eco improves.. I’ll keep you posted.

 

if some gets a thermostat replaced I’d love to here the details

 

 

 

[MikeL]

Put a new throttle body in, it took care of the hesitation but not the all the EV issues.  This model Fusion has two O2 sensors, they are on back order.  I understand from a Ford Tech that these are the most common issues with the Ford Fusion, so I am going there first.  My dealer gets $178/hr diagnostic fees.  I would rather use that  money to replace parts in a guessing process than have my car sit for a week at the Dealer only to hear they could not find a problem [again]. The Throttle body was  an easy install took 15 minutes with the OEM throttle body. But it took the vehicle over an hour to learn the new mixture before it went into EV mode again.  Still not reverting to EV when below 45 mph on a deceleration.  Now going EV at backups and moving off lights [ from full stops].

[Campenella]

Great thread.  I commented on 12-14-18 with the same problem.  Car sat at the dealer for a week.  "no codes = no problem" from the Hot Line.  Look forward to seeing what happens.  It is really cold here in WI so it will be a while before temps get over 50 but would like to solve the issue.  Thanks everyone for sharing.

[Campenella]

Is it better to replace (due to pat Ford issues) the throttle body or clean it.  I am assuming this will cure the hesitation issue when I press on the foot pedal.

 

[DiNGoD]

I am also an owner of a 2010 Fusion Hybrid with the exact same problem. It has got progressively worse over the last three winters and now my EV doesnt come on at all until car has been driving for hours. I have had it into the dealer and they cannot diagnose the problem.

I am running in Empower Mode and my thermostat light thingy does turn green but the EV doesn't engage. Capt K-9 might be on to something regarding the thermostat. How much does that cost to replace??

 

Absolutely love my Fusion btw... Thats why I still drive it! :-)

[jzavadil]

Three weeks at the dealership and they just called me to say they give up. They tried resetting and reprogramming "things" as recommended by the engineers at Ford, no change. The dealership agrees there is an issue, they just don't know how to fix. Ford told them it might be due to the cold (implying that I am using so much heat/defrost that the engine can't go to EV - wrong), or it might be due to aggressive driving (lowering MPG - wrong again), or that it might be due to the age of the car (??). Kind of pisses me off (at big Ford, not the dealership) that they would not want to dig deeper and solve this problem, being that it will probably start happening to more of their hybrids. Frustrated. Going to get the car back tomorrow and just live with it I guess. I wonder if Ford reads these Forum posts?

[Automate]

Someone in the Fusion Hybrid forum had to pay $407 but was able to get 90% of the EV power back after having the dealer "rebalance" the battery cells.

http://fordfusionhybridforum.com/topic/12638-wont-run-in-ev-mode-ice-kicks-in-immediately/?p=108946

 

[allen84]

Today, was probably the coldest day I've experienced with my 2010 Fusion Hybrid (-37 C,  -34.7 F).   Also, The EV not kicking in is getting worse (Heck, I haven't even driven in EV mode in the past 2 winters now.  This year is the worst).     So far, the engine was always on for over 3 months.  (except on some days, when it was 0 C,  32 F or a little above. IF I'm lucky, after 20 mins of driving, the EV mode comes on, when stopped at a light only.)

 

Well, 1 thing that is miraculously lasting a very long time, is my 12v AUX battery.   I haven't ever changed it since owning the car.  It starts every time, even in this insane cold.

 

Final drive time tonight:

 

21 km - 2.2 L gas consumed (13 miles - a little over half a gallon of gas)

 

So not used to having gas being guzzled in a long time.  It's weird.  At least gas prices have been cheap as of late.

Edited January 31, 2019 by allen84

[eGuru]

While you can still get reduced energy out of a Li ion battery at temperatures below freezing, the problem is that charging them at anything below about -10C needs to be very slow in order to prevent damage to the cells.

At about -30C, charging needs to be limited to about 0.02C (50 hours charge time).

 

Seems that a lot of FFH owners are learning something about their vehicles during this colder winter.

[akirby]

1 hour ago, eGuru said:

Seems that a lot of FFH owners are learning something about their vehicles during this colder winter.

 

And this is why full BEVs aren't going to take over the world in the next few years at least outside tropical climates.   Too much range loss in the cold.  I wonder what the range is on a Chevy Bolt at -20F?

[ICEY]

I have the same issue as jzavadil. The car is currently at the dealer and between their tech guy and some hotline calls to Ford they can’t figure it out. I am beginning to think that the car thinks it is warmed up enough when in fact it is not. 

Even though in Calif. we have generally higher temps there have been several days of 40-50.  I’ll get it back next week and see what happens as outside temps start to warm. Have had this car since new and now 108k. 

I am surprised that Ford can not figure this out. I have talked to them about temp. as a possibility  but don"t think anyone there has an open mind to that possibility. 

 

Frustrating.