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Mileage issue and revving engine

4076 Views 14 Replies 12 Participants Last post by  Naughtysauce
Hello everyone, I'm really grateful for this forum. I purchased a 2019 Clarity plug-in hybrid in October with 13k miles. Almost immediately I noticed that when the battery power is low (2 bars) the engine gets really loud, even at low speeds of 10-20 mph. I took it to the dealership and they said that they didn't find any problems.

The second issue is: with a full tank of gas and a full battery the available mileage is always 270 to 273 miles. I get 41 miles on battery and the rest is gas.This is obviously far below what's advertised. I am really shocked by this. I got over 320 miles out of one tank of gas with my 2001 Honda Civic. Granted, that was a manual transmission. I expected this car to be at least as fuel efficient as my 20 year old car. I have the maintenance records and it appears that the previous owner had all of the required maintenance done. None of the paperwork mentions these problems. Has anyone else had the same issues? Thank you for your help.
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Hello everyone, I'm really grateful for this forum. I purchased a 2019 Clarity plug-in hybrid in October with 13k miles. Almost immediately I noticed that when the battery power is low (2 bars) the engine gets really loud, even at low speeds of 10-20 mph. I took it to the dealership and they said that they didn't find any problems.

The second issue is: with a full tank of gas and a full battery the available mileage is always 270 to 273 miles. I get 41 miles on battery and the rest is gas.This is obviously far below what's advertised. I am really shocked by this. I got over 320 miles out of one tank of gas with my 2001 Honda Civic. Granted, that was a manual transmission. I expected this car to be at least as fuel efficient as my 20 year old car. I have the maintenance records and it appears that the previous owner had all of the required maintenance done. None of the paperwork mentions these problems. Has anyone else had the same issues? Thank you for your help.
First off, where do you live? Is the weather cold there? Are you quoting the numbers from what the car is telling you or from actual measured miles? When it’s cold do you use cabin heat? How many ICE miles have you put on the car? EV miles?
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What's the tire pressures?

"Really loud engine" typically means new (hybrid) owner not accustom to ICE running at higher rpm than "typical" for given road speed. Keep about 5+ EV miles in the battery. Not allowing the EV portion to completely drain helps A LOT with this while running in HV mode. 41 miles EV isn't unusual (we're getting the same on ours); especially if it involves high speeds (highway commuter, etc).

Want to see these numbers go up? Slow down and wait for warmer temps. :)

HTH
Welcome to the forum.

with a full tank of gas and a full battery the available mileage is always 270 to 273 miles.
273 miles sounds a bit low compared to my experience in Massachusetts. It would be useful to know your usual driving conditions e.g. highway or under 40 mph, cruising or stop-and-go, level or hilly, long or short.

Also, what ECON / SPORT / HV / HV CHARGE settings are you using?
I got over 320 miles out of one tank of gas with my 2001 Honda Civic. Granted, that was a manual transmission. I expected this car to be at least as fuel efficient as my 20 year old car.
Fuel efficiency is usually measured in miles per gallon of gas. Maximum range is a different number, and the Clarity's range is limited by its small gas tank. To play with some numbers:

The 2001 Honda Civic fuel tank spec is 13.2 gallons. If you got a 320 mile range, that's about 24 MPG. (After 18 years, my '97 Civic manual was getting about 31.5 MPG. With its 11.9 gallon tank, that's a maximum range of about 375 miles.)

The Clarity has a seven gallon tank, so your gas-only mileage looks like about 33 MPG ((273-41) / 7). That's 37% better than the 2001 Civic, even though the Clarity is larger and heavier.

My Clarity predicts about 260 miles on gas, or about 41 MPG. However, we have not filled the tank since we bought it seven weeks ago, so that estimate is rather shaky.
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Yes, check you MPG, not distance per tank. My Prius Prime could go 550 miles from full to walking with a full charge and full tank, but it was 11 gallons, not the 7 in the Clarity (and much, much lighter car). My electric range varies greatly with hills and speed. I drove the car from So. Utah to Seattle last month. Only charged the car twice (to start at home and at my brother's house to leave). I averaged 45 mpg for the 2200 mile trip (and that included a lot of 80 MPH freeway speeds).
The second issue is: with a full tank of gas and a full battery the available mileage is always 270 to 273 miles. I get 41 miles on battery and the rest is gas.This is obviously far below what's advertised. I am really shocked by this.
Ok, let’s make a possible scenario. The previous owner of the car was not too concerned with economy. He drove at 80mph on the highway, made jackrabbit starts in town and really didn’t get good mileage. Now, the computer in the car has been “taught” according to the way he drove the car. And the computer says that according to the way he drove the car it will have a range of about 270 miles. But now you, the new owner, drive it differently. You drive 65mph on the highway, don’t use the cabin heat or AC overly much, make nice slow and easy acceleration in town, anticipate stops and allow the car to slowly decelerate to make the most advantage of the regenerative braking. The computer in the car now says, is this really true? I’m not 100% convinced yet. So as you continue to drive it in a conservative manner the computer will gradually recalculate the estimated range. Remember, too, that it is an estimated range and it’s based upon past driving habits. Just to whet your appetite, here’s what I got on a almost new Clarity shortly after I purchased it. I’m pretty sure it can do even better than that too. So let’s give it a little time and see what you can get yours to do.
Speedometer Odometer Trip computer Gauge Vehicle
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I purchased a 2019 Clarity plug-in hybrid in October with 13k miles. Almost immediately I noticed that when the battery power is low (2 bars) the engine gets really loud, even at low speeds of 10-20 mph.
Ok, here’s a second scenario. We all know that lithium batteries do not like to be discharged completely. Doing so can damage them. That’s probably why your gauge shows two bars when the ICE finally kicks in. Maybe that’s around 10% of its capacity. So you’ve been driving around on electric for some time. The actual charge started out at 100% (well probably not really 100% because lithium batteries don’t like to be overcharged either). The ICE has not been running at all. The engine is cold. When your batteries reach around 10% charge the computer says, alright that’s about it for the batteries, we need the ICE to take over now. So it starts the ICE but since it’s cold, the computer knows it should warm the engine up before putting much load on it. Meanwhile, you’re still driving the car on electric and the charge is going below 10%! Nine percent, eight, seven, six… The engine finally gets warmed up and the computer sees that the battery is almost fully discharged! The computer says, OMG this can’t happen! I’ve got to do everything I can to get this battery charged back up and provide power to the electric motor so you can keep driving it. So for awhile the engine cranks out a lot of energy in order to accomplish both of those things. So not only is the engine revving at high RPM but it’s doing so under heavy load. So it will be noisy for awhile until the computer is satisfied that the battery charge is up in a more comfortable range and there’s no chance of discharging it to zero.
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Ok, let’s make a possible scenario. The previous owner of the car was not too concerned with economy. He drove at 80mph on the highway, made jackrabbit starts in town and really didn’t get good mileage. Now, the computer in the car has been “taught” according to the way he drove the car. And the computer says that according to the way he drove the car it will have a range of about 270 miles. But now you, the new owner, drive it differently. You drive 65mph on the highway, don’t use the cabin heat or AC overly much, make nice slow and easy acceleration in town, anticipate stops and allow the car to slowly decelerate to make the most advantage of the regenerative braking. The computer in the car now says, is this really true? I’m not 100% convinced yet. So as you continue to drive it in a conservative manner the computer will gradually recalculate the estimated range. Remember, too, that it is an estimated range and it’s based upon past driving habits. Just to whet your appetite, here’s what I got on a almost new Clarity shortly after I purchased it. I’m pretty sure it can do even better than that too. So let’s give it a little time and see what you can get yours to do.
View attachment 854
I can't say for sure as a 3-month owner, but I would suspect this theory is correct. I filled the tank for the first time the other day, and after charging the battery the system said I had well over 400 miles total range. I have been driving my Clarity very conservatively since purchasing it new, so the system predicts I will get more range than an aggressive driver would.
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I can't say for sure as a 3-month owner, but I would suspect this theory is correct. I filled the tank for the first time the other day, and after charging the battery the system said I had well over 400 miles total range. I have been driving my Clarity very conservatively since purchasing it new, so the system predicts I will get more range than an aggressive driver would.
This is correct!

My Clarity gives me 425 mile range when fully tanked and charged.
I drive like an old man so no youthful spirited drives.
But then I get 50-65 miles per charge which is above most others.
Hello everyone, I'm really grateful for this forum. I purchased a 2019 Clarity plug-in hybrid in October with 13k miles. Almost immediately I noticed that when the battery power is low (2 bars) the engine gets really loud, even at low speeds of 10-20 mph. I took it to the dealership and they said that they didn't find any problems.

The second issue is: with a full tank of gas and a full battery the available mileage is always 270 to 273 miles. I get 41 miles on battery and the rest is gas.This is obviously far below what's advertised. I am really shocked by this. I got over 320 miles out of one tank of gas with my 2001 Honda Civic. Granted, that was a manual transmission. I expected this car to be at least as fuel efficient as my 20 year old car. I have the maintenance records and it appears that the previous owner had all of the required maintenance done. None of the paperwork mentions these problems. Has anyone else had the same issues? Thank you for your help.
Use HV mode to keep EV full so that it doesnt go so loud and get longer mileage on rank of gas
Hello everyone, I'm really grateful for this forum. I purchased a 2019 Clarity plug-in hybrid in October with 13k miles. Almost immediately I noticed that when the battery power is low (2 bars) the engine gets really loud, even at low speeds of 10-20 mph. I took it to the dealership and they said that they didn't find any problems.

The second issue is: with a full tank of gas and a full battery the available mileage is always 270 to 273 miles. I get 41 miles on battery and the rest is gas.This is obviously far below what's advertised. I am really shocked by this. I got over 320 miles out of one tank of gas with my 2001 Honda Civic. Granted, that was a manual transmission. I expected this car to be at least as fuel efficient as my 20 year old car. I have the maintenance records and it appears that the previous owner had all of the required maintenance done. None of the paperwork mentions these problems. Has anyone else had the same issues? Thank you for your help.
Don’t forget it is only a 7 gallon tank.
Tank size jumped out at me right away too. A Clarity with a 13g tank would be something to see though, even if not much use for me personally.

Having now 6 months with the car in NJ weather, I've seen a big drop in the numbers due to the cold as expected, but haven't done any hard measurements. I'm pretty gentle on it and virtually all miles have been EV, I'm not dealing with hills and so on. I do full blast the heater when I feel like it. I knew all about how things go with the battery before I bought mine--I'd been nagging dealers for a deal for 2 model years before I could get it to happen--and it works out well enough for me.

Can't speak to the condition of someone else's car bought used or how the car has been driven, but if purchased in October you should have much better days ahead. At a glance 41 EV miles in October may be perfectly normal depending on temps where you live and a good indication the car is fine. What I would do is sit down with the manual and go through all the settings and information about your car - it's boring and a lot of folks skip it, but there are a lot of good things to know in there if you really want to get the most out of your car.
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Use HV mode to keep EV full so that it doesnt go so loud and get longer mileage on rank of gas
An argument can be made that when in HV+, or otherwise running at higher RPM, the ICE is running closer to it's ideal power band. Mileage on the ICE may be better at those higher RPMs. Could be a design decision to sacrifice efficiency a little, in order to keep ICE noise at a lower level.

This was certainly the case in my 2011 Volt. On long trips, I'd cycle between Mountain mode and the regular (deplete the battery to near zero) mode, even on flat terrain. Mountain mode increased the "reserve" in the battery to ten more miles, by running the ICE at max RPMs to get it there. This would increase my gas mileage by about 5%, as compared to leaving the Volt to do its own thing. I'd need to be vigilant in switching back and forth at about two miles on the battery, though, because it would stop showing EV miles on the display if I let it deplete to "zero" battery and turn on the ICE itself. It would still allow me to do my thing, but make it much more difficult to keep track of what was going on with the battery.
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Hello everyone, I'm really grateful for this forum. I purchased a 2019 Clarity plug-in hybrid in October with 13k miles. Almost immediately I noticed that when the battery power is low (2 bars) the engine gets really loud, even at low speeds of 10-20 mph. I took it to the dealership and they said that they didn't find any problems.

The second issue is: with a full tank of gas and a full battery the available mileage is always 270 to 273 miles. I get 41 miles on battery and the rest is gas.This is obviously far below what's advertised. I am really shocked by this. I got over 320 miles out of one tank of gas with my 2001 Honda Civic. Granted, that was a manual transmission. I expected this car to be at least as fuel efficient as my 20 year old car. I have the maintenance records and it appears that the previous owner had all of the required maintenance done. None of the paperwork mentions these problems. Has anyone else had the same issues? Thank you for your help.
What you're describing is perfectly normal. 2 bars left means the battery is empty (it leaves 2 bars there for the health of the battery)and the "generator" will kick on. The gas generator will be loud and constantly reving because there is no charge left so it has to run longer/harder to keep you driving.

As far as the HV range is concerned, my first advice to you is to unplug your 12 volt battery for at least 2 hours, I had an issue w/ mine when I first bought it and it fixed it. If that doesn't work, what are your driving habits? Are constantly driving the car w/ out charge or with? This makes a big difference because in my range test, without a charge, the car gets about 35mpg and w/ a 7 gallon tank, you'll be getting around 245 of HV miles. If you are driving w/ a charge, in my testing, I was consistently getting 42-45mpg which yields around 300 miles per tank.
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