I have a 2018 Clarity. For some reason, the past several times I have driven on the freeway with the ICE running when I start to climb an incline - not a steep one - the engine sounds like it's gonna ram through the windshield. It SCREAMS in pain! I have 63,000 mi on it and don't remember hearing the engine being so noisy. Has anyone else had this problem?
It’s normal. People call it “angry bees”. It is loud AF, and sounds like the engine is trying to kill itself……and you!
I noticed it the first time I drove up a hill. I had read about the "angry bees" before purchasing and was disappointed to find out how noticeable it is in real life. Fortunately, 95% of my driving is in EV mode only and that is why I bought the car.
I haven’t noticed that. I’m more inclined to think they (those who claim this) want that to be true….but I can’t tell any difference. I’m not thinking it’s a compression issue, which is all “premium” gas would help.
I've heard ppl comment on the sound, but I don't find it much different than a 4 cylinder econo car going up a hill at 80mph... seems it's more just a stark difference to the usual quiet nature and the fact engine rpms is not directly tied to accelerator pedal angle etc. (I'll qualify my comment to say I only drive east of the Mississippi, so our steepest grades are nothing compared out West...)
That's called an "Italian tune up". But seriously, it's actually beneficial to run well maintained engines at high rpms once in a while, hence the somewhat derogatory term. I've found that engine rpm is highly dependent on battery state of charge when going up hills. If I have 60% or more, the battery contributes significantly so the engine doesn't have to work as hard. If the SOC is low (less than 40% or so), the engine screams because most of the power is coming from the generator. This makes sense because the engine can run continuously at over 5000 rpm for a while without damage but depleting the battery will damage the battery. The BMS is simply trying to do the least damage as possible to the overall system.
Remember in hybrid mode, the engine will run to try to keep the battery at a stable level. In winter with the heat running and going up an incline, you're burning a lot of juice, so the engine is going to be noisier.
Just think of a small generator, the kind used by RV campers. They rev high when under a load. That's what is happening in our Clarity cars under certain conditions. It's perfectly normal.
Under heavy load, such as going uphill at high speed, the engine behaves as an inverter generator. It is making electricity and RPM’s vary depending on demand. It is trying to maintain the battery SOC set point and provide electricity for the motor to drive the car forward. The sensation is similar to a vehicle that actually has a continuously variable transmission. There is no direct correlation between engine RPM’s and vehicle speed or level of acceleration. We’ve all had different experiences with the car and there are a number of variables that determine how the car behaves. There is a 2 mile uphill, maybe 4%, stretch that I drive regularly. When the trip cannot be completed in EV, I’ll deploy HV for this stretch. HV needs to be initiated at least 5-6 miles before reaching the incline. It needs ~3 minutes to warm up and 3-4 miles to restore the set point, since it was operating in EV while warming up. If I’ve timed it correctly, the car covers the hill with a minimal amount of high revs. On a long trip with random hills, it will be hit or miss with as to where the set point is when a climb begins. When I do experience higher revs, I just remember I’m driving a Honda and I’ve followed the recommended oil change intervals, so I don’t worry about what the engine is doing or the possibility of it being damaged.
Angry bees are not a myth, it happens when the car tries to maintain battery charge (or is out of batter) and the engine cannot get in the direct drive mode (speed too low). The workaround is to put the car in EV mode briefly and then switch back to HV again. You sacrifice about 2 miles of EV range but hopefully go over that section of incline. Premium gas also makes the engine run smoother, but it won't result in lower RPMs.
I live in the mountains, I found putting it in HV mode with 7 miles or so left of range tames the angry bees. Also have the engine come on before the hill so it's warmed up.
Will this workaround engage Engine Drive Mode when the speed is too low, below 45 mph? Will Engine Drive Mode remain engaged under moderate to strong acceleration?
No, but the car draws from the battery for about 2 miles after engaging the HV mode, that results in lower RPMs. The engine drive will disengage under strong acceleration, but for short periods the car can draw from the battery. Angry bee happens when there is a sustained high demand and direct drive cannot engage. Also if you are dealing with a relatively short upgrade, you can just do it in EV mode. With a full battery Clarity can climb about 4000 ft in 20 miles using a full battery. They you can use HV Charge on the way down to recoup the battery.
It changes spark plug timing, most modern engines run smoother on premium gas. In Europe Honda REQUIRES unleaded 95 RON (roughly US 91 equivalent) for the 1.5 naturally aspirated hybrid engine: https://www.honda.co.uk/cars/new/jazz-hybrid/specification.html Most Americans are allergic to premium fuel, so carmakers recommend 87 even though the car runs better on premium.
Lol, I hope you’re trolling…..The whole continent of Europe, eh? Changes spark plug timing, Seriously…..
Taming the Bees: - Always keep some EV range (not zero). I tend to save EV for hills (the EV motor in Clarity is stronger which may be counter-intuitive). In all events I never let EV range go below 10 miles. - Hit the HV button briefly to go into HV mode. If the sound gets loud and you like, briefly go out of HV mode, then back in to change the set point. Or if you have adequate EV range for the hills, just switch to EV when going through the hills and back to HV when mostly flat. - If your car seems to have bees often and they're loud, you might consider "rebooting" your car (only if you have the problem frequently, or if you notice EV range goes down to zero with HV on). Reboot == remove the negative 12v battery terminal and replace it. Car will complain next time you drive, just go 15 miles and everything will go back to normal. - As others have said, even loud angry bee sounds won't hurt the car. If you have no interest in managing the bees, just let them be angry. It's not a big problem. I hate that sound, so I do manage my bees with the tips above. My car had a problem where even with HV mode on, my EV range would consistently go down. This is normal to lose a few EV miles but not have it go from say 34 EV miles to 0 when HV is on. So I had that issue. I also had angry bees on most every drive. After the "reboot" KentuckyKen recommended to me my problems went away.
