We've had our Mariner for a couple of weeks now (about 600miles) and I've read just about every thread I could find but I really can't get any improvement. I live in Philadelphia so 95% of my driving is in the city....we are talking stop and go, stop signs and traffic lights at every block. I drive almost exclusively in L and accellerate slowly maximizing my usage of the battery in EV mode and also try to shift into D or N to coast to a stop on long stretches when the battery is full. Part of my problem is the number of short trips which I know is not ideal due to engine warm up. But it seems that I can get great battery usage for most of my drive, but the last 1/3 or 1/4 of it the engine seems to kick in to recharge the battery, often at idle. I'll be getting around 33mpg...but then when the engine kicks in to recharge the battery I quickly drop to 26.8 or so. I know there is a break-in period and I should see some improvement as we approach 3,000miles but I'm wondering what else I can do? Should I try to let the engine come on during more acceleration to avoid idle charging? What should I be looking for on the energy flow screen?

I haven't really had much chance to get out on the highway to try to pulse and glide or coast. I read all of those posts as well but was hoping someone could just give me a real simple "how to".

 

Your MPGs are not bad for the low mileage your Mariner has and the fact that it's an All-Wheel Drive (AWD) as all Mariner Hybrids are.

I'm still learning myself (3224 miles, purchased March 6 '06), but can attest that there's a definite break-in period -- for both the vehicle and the driver. The Ford Escape Hybrid Manual recommends not computing/tracking MPG until 1,000 miles at minimum, and preferably not until 3,000 miles. Some of that is engine break-in, but I suspect it's just as much a factor of "the driver won't have picked up enough fuel economy friendly habits until about 1k to 3k miles." My miles per gallon still fluctuate widely depending on what I'm doing and how I'm doing it. My last tank was just shy of 32mpg due to not driving with fuel economy in mind and having to drive through a much more congested, light-controlled area (our medical center) to visit my mom in the hospital. I carried others in the vehicle on most trips, but the type and nature of the driving is more the key.

I do most of my ordinary driving in suburbia. While there are many lights and stop signs, there are also some good coasting areas (either coming or going; obviously a nice descent on a trip out is going to be a hassle ascent on the way back.) When a tank has mostly this use on it, I've gotten just slightly over 37mpg but not until I'd cracked the 3000 mile mark on the odometer. Others get that easily early but I figure I'm a pretty typical new hybrid driver. I don't even do most of my driving in "L", finding the 'engine braking' a little too aggressive for normal driving; I use it during descents and to start slowing the vehicle when approaching a stop.

Just drive the vehicle and experiment. That's the best way I've found to decide what works or doesn't work with your vehicle, type of driving and circumstances. Without trying, my vehicle does 32-33mpg now, but the "without trying" part is a little disingenuous since I am doing some fuel economy-minded things when I drive but they've become habit now (like downshifting to "L" on a steep descent that others speed down or ride their brakes on; like coasting for as long and far as possible; etc.)

 

First of all, relax. Take a deep breath, let it out, and remember, you've taken a lot of great steps, you don't have to reach for the brass ring quite yet. Give yourself time for just being in the saddle. Most, if not all of us have crappy tanks for the first four or so tanks.


Unless overcharge is a problem (ICE coming on), you may want to switch that, and drive in D, and coast and stop in L. This is early on for you, so feel free to experiment. What works for me, or Gary, or anyone else may not work for you simply because of drive/commute differences or other factors.


Sounds like an energy management issue. (See next suggestion) Also, how often do you reset the FE display? If you reset it every trip, or if you're early in a tank, that can also cause drastic MPG display loss, as there's less miles, so any change means more, but that doesn't mean anything's wrong.


You have the energy flow screen? Check to see how charged the battery is. If you're running on sparks (A sliver of green on the battery display) towards the end of your commute, that'll be why you've got so much idle charging. Energy management can be a very important part of driving. I do a lot of stop and go, and part of maintaining good MPGs is knowing when to turn the ICE on and when to just EV it. After the initial warm up period, unless you've drained the battery, it's freezing, or it's very wet, you shouldn't have to worry about idle charging at all. If it's not following one of those, and it's often, you may want to have it looked at.

If it is an energy management issue, experience is the best way to get around that, learning for yourself when you should press the ICE into service, and when to let the battery handle things.

You can pulse and glide or boost and coast at practically any speed. Personally I prefer Boost and Coast, because that seems to work for me. Boost and Coast is essentially exactly what it sounds like. You accelerate to above the speed you want to go, then coast, shifting into N if you so desire, and coasting along, then repeating the process. Pulse and Glide is similar, but far harder to do in the FEH/MMH. You accelerate, coast, then use your prefered method (Double tap, L) to ICE off, then EV maintain your speed.

Give yourself time to figure out both how to drive your MMH and the MMH to figure itself out, don't fret, you seem to be on the right path. I feel somewhat obligated to mention the FEH FAQ, there's some other little tips in there that may help as well. (Tire pressue, for example) Most people see improvements at 3, 8, and 12K, so don't expect too fantastic a tank at 600 miles. Compare for example, my second tank at 29 MPGs to a year later, where I'm on my third tank over 36 MPGs, I haven't changed that much in my overall techniqe, just some minor stuff, and a lot of experience for both the vehicle and myself.

Also, it may help if once a week, or once every few days, you can take her out for a longer drive, especially if you're draining the battery often, but that's going to depend more on the situation that you're in more than any other factor.

As always, your mileage may vary, but enjoy!

 

I don't reset the FE very often so it isn't that. I think, as you said, that I am draining the battery with too much EV because of all the stop and go traffic. I'm in EV much of the drive and there is little to no chance for coasting or "motor braking" to recharge. Towards the end of my short commutes I tend to have very little juice left and the ICE kicks in fairly often while I'm sitting at red lights. I guess I need to watch the battery meter a little closer and let the ICE come on sometimes during my drive rather than stay EV. It makes sense that driving with EV and ICE is superior to an idle ICE charge at a red light! I'll keep on truckin' I guess. Oh, and I've read the FAQ twice.

 

Tim, get the ICE off before you stop at lights and put the shifter in "N". The ICE will not restart till you put the shifter in "D" or "L" when the light turns green. This has been dicussed here many times and it is aso stated in the PCM/ED shop manual under "Neutral Mode". Under 6mph, shifting to "N" will keep the ICE on or off depending on the state it was in at the time of the shift under 6mph. I use this all the time.

GaryG

 

Thanks Gary. That is a tip I missed.

 

The caveat to that is that if he's drained the battery, the ICE isn't going to go off as he slows, so switching to N will keep the ICE on anyway. Only if he's got enough charge for the ICE to switch off can he use that technique.

Since it does seem to be energy management, try to focus more on using the ICE when you're moving, and regen/ICE off when you're stopping/slowing. It'll take time to figure it out for your commute, but I'm confidant you can come up with a system that'll work for you.

For example, I use Michigan Ave in Dearborn twice a week. The lights are impossibly timed, so for the 15 lights, you have to stop, regardless of where you come in for 12 of them. (Though where you come in makes a difference on which 12 you stop at.) I've figured out that for lights 1 and 2, to EV it. To light 3, I ICE (and hybrid drive) it. 4, 5, 6, 7 I EV. 8 and 9 I ICE. 10, 11, 12, EV. 13-15, ICE, then EV into the parking lot and parking spot there. I arrive with a low charge, but I don't have to worry about it, and never lose and sometimes gain a .1 MPG. Going the other way, I end up getting onto I-94, so if the battery is drained, I get really crappy MPGs as it's both accelerating to 65 MPH and recharging the battery. With careful energy management, I get onto the epressway with a greater charge, and I spend less time recharging on the expressways, and minimize bad MPGs.

As always, your mileage may vary. But have fun finding out, and don't be afraid to experiment.

 

Hey Gary, can you tell me more precise where in the PC/ED you found the info? i have tried to look for it, but cant find it. also i would be careful about shifting into "N" just because there is an onboard computer that records everything and if something goes wrong with the tranny, i could, depending on the circumstance, maybe, possibly void the warranty.

 

Hi Bethany

The neutral gear mode information is found in the '05 PCM/ED manual in the Hybrid Electric Control Software section on page 1-77.

Shifting to neutral is an electronic control of the center axle disconect joint. The patent if you need to read more on the subjest is located at: http://www.freepatentsonline.com/6793034.html

If there was any doubt that shifting to "N" caused any damage, I would stop. Ford engineers have said that shifting to "N" would only prevent regen from charging the battery. Above 6mph, the ICE can start or stop so the small generator will charge the battery if needed, and run the A/C.

Gliding in "N" can improve you MPG a great deal and it is also stated the owner's manual, the FEH can be towed safely in neutral with all four wheels on the road up to 75mph. There are no operating warnings on the use of neutral that I could find, and my FEH has had no issues so far.

GaryG

 

I was wondering if you could please tell me ( or show me ) where is says the product at the follwing link is part of the Ford Escape Hybrid. Thank you. I agree with the rest of your post. I've noticed no harm from coasting in N in my vehicle.