Not happy with first road trip

[bpratt]

After about 2000 miles on my car and no gas put in, I took my first road trip from Salt Lake City to Las Vegas and back. My EV range showed 53.4 and my HV range showed 1000 after I filled up. The elevation at my house in Salt Lake City is about 4800 feet. Las Vegas is 2000 feet and there are a few mountain passes that are about 6700 feet. The speed limit between SLC and Vegas is about 20% at 70 mph, 15% at 75 mph and 65% at 80 mph.
I drove EV about 4 miles to the freeway and put the car into HV mode once I hit 50 mph and left it there until we pulled in for gas. Once I got back on the freeway and hit 50 mph I put it back in HV mode. We had 3 adults and about 50 pound of luggage for less than 500 pounds of extra weight.
The problem I had was that the engine was running at high speed and was very noisy for about 70% of the trip. I spent several years when I was younger racing cars with a tachometer and got very good at estimating engine RPM by listening. I felt the engine was running between 4500 and 6500 RPM for most of the trip and was very noisy.
I went into INFO and then Vehicle Energy on the display. When the clutch is engaged and the engine is connected directly to the wheels, a little circle appears where the lines cross and go to the wheels. I found the clutch was only engaged about 15% of the time. When it was engaged, the engine was quiet.
I didn't get a chance to charge the car in Las Vegas and when I got home the EV range had dropped to 17.2 miles.
I feel this is a great car for around town and a poor car for freeway driving.

 

[Steven B]

I don't think your experience is typical of normal highway travel. I had no instances of such behavior during a 1900 mile mostly interstate trip a few weeks ago (vehicle similarly loaded). The times the engine should run at higher RPMs: 1) when the driver has intentionally (or unintentionally) put it into HV Charge mode by holding down the HV button, 2) when the battery has been fully or mostly depleted, 3) when travelling a steep incline and being asked to maintain speed.

 

[Kendalf]

I agree with @Steven B. Is it possible that you unintentionally engaged HV Charge mode? In all my experience with freeway cruising with HV Mode on, the engine is near inaudible; certainly no more than any other 4-cylinder vehicle.

If you're cruising above 50mph in HV mode, the clutch should be engaged most of the time. It will disengage if the engine is instead powering the generator to charge the battery, which would be the case in HV Charge mode. I would suggest testing this again on the freeway and if you can confirm that you're getting such high rpm while in HV mode, then definitely bring the car to the dealer to demonstrate, as that is not expected behavior.

 

[bpratt]

I agree with @Steven B. Is it possible that you unintentionally engaged HV Charge mode? In all my experience with freeway cruising with HV Mode on, the engine is near inaudible; certainly no more than any other 4-cylinder vehicle.

I have put the car into HV Charge mode and when you do, HV Charge mode appears on the drivers display for a couple of seconds. I originally thought I might have done that, so I canceled HV mode and did a quick single press of the HV button. HV mode appeared on the drivers display, so I know I was in HV mode.
I agree the clutch should be engaged most of the time. I found that to be the case a couple of times I drove in HV mode at 65 mph. At 80 however (actually we were driving between 82 and 84 most of the time) the clutch only engages when going on a downhill piece of highway for at least a mile. Once the road leveled out or starting slightly uphill, the clutch would disengage and the engine would race.
The battery was never depleted. Over time it would reduce but 50 miles from home it was about 20 and once we reached home it was about 17.

 

[KentuckyKen]

If it wasn’t in HV Charge Mode, then I have to chalk this up to some Claritys seem to be prone to angry bees and some not. This was not my experience when on Interstate at 65-70 mph (no major inclines, ACC used). Both when manually selecting HV and when running EV and letting algorithm choose when to switch to HV at 2 bars, the ICE was hardly noticeable. Energy display showed car cycling through the various energy flows. Even when reaching home and driving at under 20mph, I could just barely hear it running. Sounded kind of like a quiet fast idle. And I think (not sure) it even cycled on and off in stop and go city driving at destination.

So far, no one has come up with an explanation of why some of us experience the high revs and some don’t (other than the expected times that Steven B mentioned).
Maybe dealer could check if there are any error codes recorded and if so do the battery disconnect reset? It’s not typical behavior according to many of us on this forum.

 

[KenG]

Ok.... if you are driving constantly between 82-84.... you might not be this Cars demographic.... in fact if you drive these speeds constantly.... you may want to try a v8.... or return it to the dealer.... in 2000 miles, I have not experienced this, Another guy on the Clarity forum has 7000 miles and has not seen this problem.




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[Viking79]

Did it do this all the time or only going up mountain passes at 82 mph? I will be driving it back to WY in July and can comment on what I think driving 80 mph on interstate.

 

[Steven B]

Ok.... if you are driving constantly between 82-84.... you might not be this Cars demographic.... in fact if you drive these speeds constantly.... you may want to try a v8.... or return it to the dealer.... in 2000 miles, I have not experienced this, Another guy on the Clarity forum has 7000 miles and has not seen this problem.

I suppose one of the number-crunchers on here could explain how the fuel efficiency drops as a function of speed due to wind resistance. It is definitely not linear. Another solution would be to empty the gas tank and then drive 82-84 mph from charging station to charging station.

 

[KentuckyKen]

I suppose one of the number-crunchers on here could explain how the fuel efficiency drops as a function of speed due to wind resistance. It is definitely not linear.

This one I know. Wind resistance increases roughly geometrically (with the square of speed) while energy consumption increases roughly linearly with increased speed (after accounting for gear ratio changes in ICE vehicles-not a concern for us). So the faster you go not only the more wind resistance you fight but the rate of increase is also going up. So the difference of wind resistance between 75 and 85 is greater than the difference between 55 and 65, even though they’re both just 10 mph apart. End result, the faster you go the more your mpg will start to drop like a rock.
You can bet the family farm that the EPA numbers on our Claritys were not calculated at 85 mph!

 

[AlanSqB]

I drive 85 MPH in this car pretty regularly on I-25 and E-470 here in CO. It is going to sound like a Honda FIT having a fit sometimes to maintain those speeds. I just ignore it. 4-bangers are built to run at high revs for extended periods.

I did try the trick of using sport mode on the highway today and I have to say that the experience with ACC was much more pleasant.

 

[ab13]

At high altitude you are losing some power from the gas engine, so your engine will have to work harder. Also, if you are going up inclines, then you will require much more power than cruising. I don't believe the clutch mode is going to work well beyond cruising since it's mainly effective for mostly flat roads. So was much of the issue during uphill runs?

 

[KentuckyKen]

I drive 85 MPH in this car pretty regularly on I-25 and E-470 here in CO. It is going to sound like a Honda FIT having a fit sometimes to maintain those speeds. I just ignore it. 4-bangers are built to run at high revs for extended periods.

Then it’s just like outside the car; you can’t outrun a bunch of angry bees

 

[714hello]

What is your car's built date? Could the earlier ones have issues like the "angry bees"? That was why I choose the latest build date possible. Mine was 2/18.

 

[bpratt]

I purchased the car in late December, so I would guess the built date is fairly new. The engine ran at high rpms on both level ground and going uphill. It was a lot higher rpm going uphill but the only time it stopped racing the engine was going down hill for at least 1/2 mile. Even at 82 - 84 mph the car still got 42 miles per gallon. I do mostly city driving and I guess the next road trip we take will be in my wife's Lexus.

 

[ab13]

I purchased the car in late December, so I would guess the built date is fairly new. The engine ran at high rpms on both level ground and going uphill. It was a lot higher rpm going uphill but the only time it stopped racing the engine was going down hill for at least 1/2 mile. Even at 82 - 84 mph the car still got 42 miles per gallon. I do mostly city driving and I guess the next road trip we take will be in my wife's Lexus.

Driving over 80 mph and going uphill is going to take a lot of power. My guess is the gearing is for 80 mph on flat road. Going 85 instead of 75 results in almost 30% more drag.