Low speed engine noise

As this thread shows, I think it is a function of the situation. I definitely got the high-rev noise when I took a long trip and kept the car in Normal EV mode. Once the battery drained, it had the loud high-rev sound every now and then as it (I guess) charged the battery.

 

I drained my battery on the interstate and Car went into “HV” mode automatically and I heard no angry bees (and yes, I had my hearing aids in!) at 60-70 mpg and none at end of trip in low speed subdivision driving. The ICE was running at times but not at an excessive rpm/noise level.
So it may not be situational. It may vary car to car. We need more data.

 

I had an appointment to get mine looked at, but canceled it. Am a bit nervous to have the techs mucking about under the hood.

 

Mine revs up too loudly also when the car goes into hybrid mode. When accelerating normally from a stop sign the engine revs up, only it sounds like when you press and hold the gas pedal on a regular car when it’s in park. I get that it sounds like that because the engine is simply turning the generator, but I feel that there is enough power in the battery to assist in propelling the vehicle from a stop without having to make the engine rev so much. It would be understandable going up a long hill, but not in normal city driving. I also get the overly loud revving on highway driving every time I moderately accelerate. The 2 or so kW of capacity in the battery pack remaining when the vehicle switches to Hybrid mode should keep the engine from revving so easily on normal takeoffs and moderate accelerations. Since this seems to be so widespread I’m hopeful there will be a software fix in the future.

 

Well, this is probably not the car for you then. It doesn't have quite as advanced a transmissions system as the Volt so it seems to have the engine just run at a couple of speeds. Here are the one's I've noticed:
- Idle Speed: This is what you get if you're at the stoplight after accidentally pressing too hard on the gas.
- Middle Speed: This is when you're cruising along in HV mode at a decent speed.
- Angry 1.5l mode: This is what you get when you're accelerating hard when the battery is low on charge. I think it's pushing the car and trying to generate electricity all at once.

The car has a tiny little engine, like a Honda Fit. It's not a sound befitting such a nice vehicle, but I think it's working as designed. The tiny little engine works like a generator, making electricity. Occasionally, it also drives the wheels. If you accelerate when the battery is low, it has to use battery to accelerate and it has to run the engine at a higher rate for some time to replenish what was used to get it back up to an acceptable buffer level.

The awkward part is, especially for those of us who are used to pure EV, is the engine noise not matching the speed the car is going. I've never had a hybrid so I'm not used to it. I have personally taken to using HV charge on my longer trips to generate enough battery charge on the highway to drive around quietly when I get where I'm going.

 

I drained my battery a few times drivers over 50 miles before charging. The ICE does rev quite high when the car was driving at under 40 mph. I think the car was trying to charge the batt and run the generator to propel the wheels at the same time. Once you drive fast enough, the ICE will drive the wheel directly and it's rpm will be a ratio to wheel rpm.

 

I will need to step up as one that has never heard the angry bee’s. I’m only a month and 1k miles in but so far just perfect.... Although,mostly EV miles.


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Ditto here, KenG.
With moderate/normal acceleration and no steep hills, I too have never heard the “angry bees”.
I have only heard Dstrauss’ “idle” and “middle speed” (which I called fast idle in another post). Idle only when battery was full and maybe it was a System Check. And fast idle when battery depleted on Interstate and when in HV mode.

 

ManKo, that 2kW remaining is at 100% depleted usable battery capacity and is the buffer to prevent Li Ion battery damage and shortened life span. So it is not available to the system to draw on. When you get to 0 EV range and 2 bars remaining the system considers the battery “dead” or fully depleted and will not draw any power from it. Thus it has to rev to put some “in the bank” to be able to draw on later so it can cycle through its most efficient modes. I’m pretty sure it’s not a software problem.

 

Drove 10 miles in Econ mode in city traffic. Battery fully charged. No radio, climate control or anything else on. ICE came on immediately, then five more times. Outside temperature about 62 degrees. This behavior is new. Did not do that until this week. 1,068 miles on the odometer.

 

This is not necessarily accurate. The ICE kicks on when the battery drops to 12%. There’s been several times where I’ve depleted the battery and I check the charge level right before plugging it in and the battery level is at 8%. That means with a little better programming that 4% spread could act as a nice buffer when the vehicle is in Hybrid mode. It certainly shouldn’t sound like “angry bees” when accelerating normally from a stop sign.

 

I'm at 30% battery, driving locally around 70 degrees temperature and accelerating normally (as compared to the cars around me) on HV and EV modes. The revving 'angry bees' come up from time to time.

 

If you look at this video, you can see that this guy is running at about 2 bars of battery and you can hear once the car gets up a little bit of speed, the revving sound that comes up. (Pretty apparent around 42s in)



Maybe it's normal? Otherwise, perhaps some people are more used to driving hybrids than others and don't notice it as much?

 

I too have not heard the angry bees after 6,100 miles. I think the key is not to let the battery drop to two bars.

 

Can you check if you hear anything if you're ~30-40% and on HV charge mode?

 

I have tried to hear the engine coming on without success. The only time I can hear the engine is accelerating a at low speed, rare as that is.

 

You know this is an economy minded forum when "Vtec kicks in" and people are annoyed. Lol.

 

I agree with you. My interest in the Clarity is mixed. On one hand, it seems great. But wondering if this noise issue is a deal breaker. I really need to make a decision because my car is on its last legs. I also preferred the roomy interior of the Clarity to the Volt. But now wondering if the engine noise with the Clarity is gonna be a problem. I'm pretty sensitive to noise, period.

 

Like jdonalds and others, I’ve never heard the angry bees high engine rev noise. My Clarity is the quietest car I’ve ever owned. I had to install an inductive hour meter so I could be sure when, how often, and how long the ICE was even on! (Too hard to hear it, and too easy to miss the HV range decrease) I’ve gone 3 months and almost 2,000 miles on 2 gal of gas in quiet roomy comfort.

Just make sure the dealer charges or at the very least partially charges the car before your test drive so you will get a real world experience. Driving off the lot on a battery that has never been charged since it was installed in the car will give a misleading impression. Switch it between EV and HV modes on the hwy and you will see if noise is a problem for you. I bet you end up buying it. It’s hands down better than the Volt which is technologically great but size challenged. It’s so small, I don’t consider it a “real” car. Let us know after your test drive.