After the PCM software update/recalibration - observations by Hybridbear

[terryb]

I guess I'm going to have to give another serious try at getting my service crew interested in my mileage. I had 23k on my '10 when I traded it and averaged 43mpg. I have 10,300 on my '13 and I'm at 36mpg. I've got 3000 since the EPM calib. change on 29 July. I'd settle for the '10 power train in the '13 shell.

[fusionTX]

I guess I'm going to have to give another serious try at getting my service crew interested in my mileage. I had 23k on my '10 when I traded it and averaged 43mpg. I have 10,300 on my '13 and I'm at 36mpg. I've got 3000 since the EPM calib. change on 29 July. I'd settle for the '10 power train in the '13 shell.

You coming to the Houston reunion? Maybe we can compare cars.

[jnissen]

How can we confirm the update was applied? I had it done last Friday but any speeds above 62MPH I can not seem to get the vehicle to go into EV only mode. I thought the update was supposed to enable this? Did my dealer just scre3w me over and say it was done or what? Please help.

[B25Nut]

Have the dealer do the update over again. It was not done correctly. With the update, your FFH should easily go into EV at speeds above 62 mph on a level road.

[jnissen]

That is what I thought. I really don't have much confidence in this dealer. I have had the vehicle in three times now with only 2500 miles on the clock. Once for a evaporator system leak, a second time for a fuel door warning related to the same evap system, and now this update that apparently was not implemented. I purposefully accelerated on the crest of a hill doing about 70MPH and backed off the throttle quickly and thought it would enter EV mode. The battery showed 3/4 charge yet the thing would not show EV mode.

 

BTW = MIleage at temps up in to upper 90's or over 100 degrees is terrible. Lucky to register 38MPG for some simple round trips. The AC on fairly high all the time is really knocking the battery down.

[fusionTX]

I guess I'm going to have to give another serious try at getting my service crew interested in my mileage. I had 23k on my '10 when I traded it and averaged 43mpg. I have 10,300 on my '13 and I'm at 36mpg. I've got 3000 since the EPM calib. change on 29 July. I'd settle for the '10 power train in the '13 shell.

I just did a round trip Houston -Wimberley, about 360 miles round trip. Lots of hills as you get closer to hill country. Averaged 37.5 for the trip. My car is not great on highway. I did several tests coming back today with stretches at 75 MPH followed by stretches at 70 MPH.

I never got out of the mid thirties. At 75, it was doing between 33 and 35 MPG. At 70, I expected much better, but really did not see a big improvement.

 

Yet my car performs very well in the city.

 

This is my first road trip since PCM update, and there are elevation fluctuations on this trip. Still, I don't see how anybody gets mid forties on a road trip.

Edited September 2, 2013 by fusionTX

[MaineFusion]

Sometimes I wish I had more city driving to see how I do there. Beyond my commute back and forth to work, which is mostly highway miles, I don't drive very much.

[terryb]

I think that falls into the category of not asking a question you might not like the answer to. I get lower mileage on the street than

at 75mph

[corncobs]

I just did a round trip Houston -Wimberley, about 360 miles round trip. Lots of hills as you get closer to hill country. Averaged 37.5 for the trip. My car is not great on highway. I did several tests coming back today with stretches at 75 MPH followed by stretches at 70 MPH.

I never got out of the mid thirties. At 75, it was doing between 33 and 35 MPG. At 70, I expected much better, but really did not see a big improvement.

 

Yet my car performs very well in the city.

 

This is my first road trip since PCM update, and there are elevation fluctuations on this trip. Still, I don't see how anybody gets mid forties on a road trip.

fusionTX I know what you are talking about since I expierenced the same on our trip to Atlanta and the coast (Charleston & Savannah) it got a bit better on you return trip.

 

I believe that after the update the car had to relearn different driving patterns and it just takes time. I don't know if I'm right but the difference between in and outbound was about 3 MPG not a lot but better.

 

On the other hand right after the update I made 3 days of 55 MPG to work in a row since the roadtrip my highest has been 54 MPG but mostly 53 MPG. The drive home has been 45 on the nose with the AC running with 90*+ temps around here last week.

[MaineFusion]

I think that falls into the category of not asking a question you might not like the answer to. I get lower mileage on the street than

at 75mph

I tend to average around 63 mpg when doing non-highway driving. Since I don't live in a major metropolitan area, I don't have long strings of badly timed traffic lights to force me to constantly start and stop.

[DrewFM]

We just had the calibration done and are seeing less mpg in short around town trips. It seems the engine runs more and the battery always seems low. any suggestioI

I had the update done. My MPG got worse at highway speeds until I stopped and disconnected both the 12v and the HVB for about 5 minutes. I reconnected the HVB and the 12V battery (in that order), and viola! Immediately noticed that the HVB indicated a 100% charge, even though it was only at 50-60% when I stopped. I can only think that after the update, the HVB on some cars needs a new reference point as to what the HVB SOC actually is? Anyway, it worked.

[corncobs]

I had the update done. My MPG got worse at highway speeds until I stopped and disconnected both the 12v and the HVB for about 5 minutes. I reconnected the HVB and the 12V battery (in that order), and viola! Immediately noticed that the HVB indicated a 100% charge, even though it was only at 50-60% when I stopped. I can only think that after the update, the HVB on some cars needs a new reference point as to what the HVB SOC actually is? Anyway, it worked.

Sounds like an interesting approach but can you give us an idea of before an after mileage? And how did you disconnect the HVB?

[murphy]

And how did you disconnect the HVB?

Fold down the right rear seat back.

Open the access panel.

That is the HVB disconnect.

[corncobs]

Fold down the right rear seat back.

Open the access panel.

That is the HVB disconnect.

Thank you that was easy enough. I actually thought about the disconnect but everything seems so complicated it was almost too easy.

[terryb]

I had the update done. My MPG got worse at highway speeds until I stopped and disconnected both the 12v and the HVB for about 5 minutes. I reconnected the HVB and the 12V battery (in that order), and viola! Immediately noticed that the HVB indicated a 100% charge, even though it was only at 50-60% when I stopped. I can only think that after the update, the HVB on some cars needs a new reference point as to what the HVB SOC actually is? Anyway, it worked.

I really want to hear that this provided some measure of mileage improvement before I pull the electronics off life support.

[arob]

Had mine done over the weekend. Trip in today was about normal, I generally vary between 50- 62MPG coming downhill to work (about 2500 foot drop in elevation), I got 55. I did notice very different behavior with much more EV mode, but then it would kick in to ICE to recharge when SOC fell below half. Usually see 36-42 on the uphill return trip.

 

Clearly, the changes will require some adjustments on my driving habits as I learn the nuances of the new algorithms.

 

Ok, A full week with the update and it seems that given my 95%+ highway driving, about 50% of which is 75MPH, and 20% deals with congestion, I am seeing little improvement.

 

I started using Trip counters to look at round trip, I am getting high 50's downhill (to work), and around 40 uphill. RT is high 40s. Prior to the update, uphill was 2-3 MPG lower, but downhill same or slightly better. So, I am not convinced it is a net benefit. Too bad you cannot switch modes on the fly...

 

All in all, I can't complain, update was free and it is not costing me anything in lost MPG. And the FFH is cutting my fuel cost by 60% over the Audi I used to drive.

[Eddie Sessum]

I wish I could leave everything alone and manually lower the EV point back to 62mph. I find on extended highway rides I get better gas milage at 70mph once the battery charges than I do at 65mph with the ev mode going on and off. I guess in a short exit to exit jump on the interstate this could be of benefit.

[MaineFusion]

Fold down the right rear seat back.

Open the access panel.

That is the HVB disconnect.

Just be careful that the car doesn't figure out what you are doing or you might be hearing "I'm sorry Dave but I can't allow you to do that."

[GrySql]

I had the update done. My MPG got worse at highway speeds until I stopped and disconnected both the 12v and the HVB for about 5 minutes. I reconnected the HVB and the 12V battery (in that order), and viola! Immediately noticed that the HVB indicated a 100% charge, even though it was only at 50-60% when I stopped. I can only think that after the update, the HVB on some cars needs a new reference point as to what the HVB SOC actually is? Anyway, it worked.

My mileage tanked after the PCM update and I read this battery disconnect idea and thought why not try it, so I did it yesterday.

No problems doing it, easy.

I didn't get a chance to drive it until today, my 75 mile trek to the Dealer for a PCM re-check, Fuel Module recall, DRL software install, MFT 3.6.2 install.

My very early drive this morning thru horrible traffic, dodging steaming wrecked cars and lunatics was difficult but the FFH acted differently.

The EV mode switched in at above 62mph on level and downhill sections, didn't jump all over the place between ICE and EV, seemed smooth and felt right. My speeds were from a crawl to 70 mph and everything in between, AC on.

Anyway, when I turned the key off at the Dealer I was shocked to see the car had achieved 44.8 mpg's for that 75 miles of difficult traffic.

That has never happened before, even before the PCM update. I like it.

I have no specific conclusions to make except the car drove much more like a hybrid today.

 

Today the Dealer is going to make sure all the systems are exactly what they should be and do the other items on my list.

[Eddie Sessum]

I don't understand how this helps being the battery meter works on a voltage reading not a static up and down calculated by use

[GrySql]

I don't understand how this helps being the battery meter works on a voltage reading not a static up and down calculated by use

Me either, but the disconnect of the batteries is called a 'hard reset', like re-starting a frozen computer.

I did say that I can't draw any conclusions between the battery disconnect and my dramatic 'all of a sudden' better mpg's.

However, my car could not break 40 mpg's before I did that - a mystery.

 

I am at the Dealer right now having them re-check everything because I feel it's the appropriate thing to do.

Either way, if my mpg's improve I will not complain even if I can't explain why.

[Eddie Sessum]

Did you have ac on during that trip and what were outside temps? I'll consider doing it depending on conditions and all. I don't remember if my 43mpg was before or after the update

[Eddie Sessum]

Did you have ac on during that trip and what were outside temps? I'll consider doing it depending on conditions and all. I don't remember if my 43mpg was before or after the update

[GrySql]

Ambient was about 70F, AC on so I didn't have to suck in all the exhaust, various speeds, never over 70mph.

I was amazed to see my SOC get charged so fast, then on one level stretch all the traffic was going 70mph and I looked down and was running in EV mode for about a mile or so.

Honestly, when I got to my destination I was expecting the usual 36-38mpg's, the 44mpg really surprised me.

I've made this trip about a dozen times and it was normal to get 36-38 going and 34-36 on the return, there is a slow uphill 1,500' elevation change going back.

Edited September 4, 2013 by GrySql

[gmarshall]

GrySql did you have to reset everything on the car after disconnecting both the HV and 12V batteries such as all of your SYNC info?