engine knock
#16
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If, however, you punch the accelerator when the engine starts to labor, it will force the engine into a lower gear and the knocking should not happen.
Thus, if, when you start to see/feel the engine laboring, if you punch the accelerator and force downshifting, I think that there is a good chance that the knocking will disappear. Also, if you are driving in Eco mode, try driving in Normal mode, which will change the programmed shift points and reduce the instances where the engine might have to labor to get the job done.
Thus, if, when you start to see/feel the engine laboring, if you punch the accelerator and force downshifting, I think that there is a good chance that the knocking will disappear. Also, if you are driving in Eco mode, try driving in Normal mode, which will change the programmed shift points and reduce the instances where the engine might have to labor to get the job done.
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#18
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Bear in mind, the hybrid has a CVT, although it has some pre-determined ranges selectable by the shift lever. It pretty much finds its own level. Mine does not knock under any conditions I've found--full throttle or light. Eco, normal or power. Regular gas, only. It could be some rattling from a loose exhaust or catalytic converter shield, or some questionable gas, but since it's designed for unleaded I doubt name brand regular would cause a problem. If it does it on premium you could eliminate the gas, and ask the dealer to check everything again.
Not any loose exhaust or cat converter...technicians identified it as knock. If I recall Lexus advises only regular in this car, correct me if I'm wrong. But, they put 91 in it and said try it.
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I'm confident in my guess that the reason why some might be seeing an issue and others won't is related to the differences in the driving styles of different drivers, and I'm also confident in my guess that recognizing when the engine is laboring and forcing the transmission into lower gearing by punching the accelerator will eliminate the issue for most. Again, even switching from Eco mode to Normal mode should also help for those who are less inclined to be able to recognize when it would be beneficial to use the accelerator to force the transmission into lower gearing.
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It definitely isn't a feature of the hybrid. My 300h doesn't knock under any condition nor did the Camry hybrid I drove for 4yrs that has essentially the same powertrain as the 300h.
It is possible that you got some bad gas from Costco but I don't know. There are gasoline additives/cleaners that you could get from Autozone or other parts stores and run thru one tank of gas to see if it resolves the issue that just several tanks of clean gas wouldn't fix.
The only other thing I could think of is that your state/city may have seasonal additives/ethanol levels that might impact the octane/performance of the gasoline. We do have this in the city I live in the summer time to combat ozone, but again I have never had a knocking issue with my cars on 87 octane here.
It is possible that you got some bad gas from Costco but I don't know. There are gasoline additives/cleaners that you could get from Autozone or other parts stores and run thru one tank of gas to see if it resolves the issue that just several tanks of clean gas wouldn't fix.
The only other thing I could think of is that your state/city may have seasonal additives/ethanol levels that might impact the octane/performance of the gasoline. We do have this in the city I live in the summer time to combat ozone, but again I have never had a knocking issue with my cars on 87 octane here.
#21
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CVT is a continuously variable transmission, which is what is used in the ES300h, while a conventional transmission is used in the ES350.
If what I'm thinking is possibly the cause of what you are hearing, it would be the result of having a "light" foot and would not be happening if you had a heavy foot.
Last edited by lesz; 05-15-14 at 03:14 PM.
#23
Lead Lap
No, it doesn't use "gears". Instead, it uses friction. I just use the term "gear" in a more general sense to refer to the gearing ratio that is being used to propel the vehicle. Perhaps, there is a better term that I should be using, but, if there is, it isn't coming to mind.
#24
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I probably should have said this in my earlier posts, but my thinking was that the sound that you are hearing might actually be the engine lugging. Engine knock and lugging can have fairly similar sounds, and they can occur under similar circumstances, especially when the automatic transmission is selecting a gear that is higher than what is called for in situations such as climbing up a hill, and that is when using the accelerator pedal to cause the transmission to use a lower gear is called for.
#25
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(Note that I'm still struggling to find the right term to use for a CVT that would correspond to changing gears with a conventional transmission. )
#26
Here's my .2 cents on this. I live in a part of my town that requires me to drive 3 miles uphill to get home everyday. It gets VERY steep once your about 70% of the way up. First off it's your car pinging obviously for a reason. I hear my car ping best when I'm passing a parked car, with my passenger window down, on the steepest parts of my climb, load on motor... (You'll hear it echo off the parked cars)
Reason being: When I don't run 91 octane. My Gs is a ***** and knows when I'm not running premium, and makes sure to know I know, she knows... LOL!
If your cars pinging, you need to raise the octane in order to raise the combustion temperature of the fuel to avoid combustion... (What causes pinging)
Certain companies make my car ping and some don't. First you need to clear the carbon deposits which aid in pinging a lot more than you imagine. It builds a heat barrier which significantly increases an engines combustion chamber temperatures. So if your running 91 or 93 and still pinging, well, not saying it's for sure! But you could have a lot of build up, or simply the wrong dam plugs or gaping. So... Run some sea foam through a vacuum line, I do half a bottle though the line, and the other half of the bottle in my fuel, read up on how to correctly do this... Wanna see what's built up? Hahaha oh you will just take a look in your rear view mirror when driving after shooting it directly through the line. It's actually very healthy for the motor and is a sufficient way to get what we can, out without actually getting in there and doing so... My car seems to like 76, and chevron... Not sure why... But... I'm not that into it to break down what additives and how much each company uses to care. I can just tell by the way she purrs
Reason being: When I don't run 91 octane. My Gs is a ***** and knows when I'm not running premium, and makes sure to know I know, she knows... LOL!
If your cars pinging, you need to raise the octane in order to raise the combustion temperature of the fuel to avoid combustion... (What causes pinging)
Certain companies make my car ping and some don't. First you need to clear the carbon deposits which aid in pinging a lot more than you imagine. It builds a heat barrier which significantly increases an engines combustion chamber temperatures. So if your running 91 or 93 and still pinging, well, not saying it's for sure! But you could have a lot of build up, or simply the wrong dam plugs or gaping. So... Run some sea foam through a vacuum line, I do half a bottle though the line, and the other half of the bottle in my fuel, read up on how to correctly do this... Wanna see what's built up? Hahaha oh you will just take a look in your rear view mirror when driving after shooting it directly through the line. It's actually very healthy for the motor and is a sufficient way to get what we can, out without actually getting in there and doing so... My car seems to like 76, and chevron... Not sure why... But... I'm not that into it to break down what additives and how much each company uses to care. I can just tell by the way she purrs
#27
Lexus Champion
So are you talking about running premium gas in your GS? Yes, I run premium on my GS too but the ES should run on regular.
Your sea foam sounds like a colonoscopy cleansing for cars .
Your sea foam sounds like a colonoscopy cleansing for cars .
#28
Lead Lap
Sea Foam? Higher octane than recommended? Both wrong IMO. Use the gas that the manufacturer recommends and NO additives. These cars should not be pinging under ANY circumstances. Uphill, downhill, light foot, heavy foot, window down, window up, etc. These engines are controlled by a computer that adjusts by the millisecond to the various conditions.
#29
Lead Lap
And that is the reason why I think that there is, at least a possibility, that what the OP is hearing is actually lugging. My suspicion that that might be the case is bolstered by the fact that the dealer's service department did not find anything amiss with the engine's operation, and that could be the result of the service adviser or technician driving the vehicle while using the accelerator differently and in a manner that was more likely to cause the transmission to be responding more appropriately relative to what was called for when accelerating or climbing a hill. While I can't dismiss the possibility that there is a genuine problem with the engine, I also have a hard time believing that, if there was a genuine problem, it would not be readily apparent to the people in the dealer's service department.