ryoo1257

I purchased a ES300h in March 2013. Starting end of September I noticed a rattle (pebbles in a tin can tumbling sound) when I went up a slight grade, accelerating from a stop, or accelerating after a brief coasting on the freeway. The first time at the dealer they said stop using Costco gas and use Top Tier. I used Shell and Chevron and there was a 80% improvement but the nuisance still continued, some days more and some days less, meaning when it rained it poured.

On the third visit to the dealer, with two specialists on a ride along of course it does not make that noise, but left it there for them to find the continued problem and they conceded it is engine knock to which there is nothing out of specs with the engine AND say that this is normal. I have never had a car do this, maybe specific to hybrids? The service advisor goes on to tell me that they filled my tank with 91 octane to help with the knock, BUT, the manual says use 87!!! The dealer is no help.

Some say this can lead to engine damage, some say only blown gasket, the dealer says no problem! A friend of mine has the same car and has no issues. Has anyone experienced and resolved this issue?

Poppa

I"m afraid I have no experience with hybrids, but I do know that a few years back I had an older Ford Thunderbird with a V-8 and it developed what I called a spark knock. I tried setting the timing back and that helped a little bit but still had the ping... then I switched over to 93 octane Texaco / Chevron and within 2 or 3 tanks the spark knock stopped completely. Just something to think about.. Good luck with it all.

Poppa

lesz

While it is probably more common for people to drive with a lead foot, it might be the case that your knocking is the result of driving with a light foot. When a car is going up a hill or accelerating and if it is in and stays in a gear that is too high, the result can be that the engine starts to labor and there is engine knocking. 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. With the relatively small 2.5 liter 4 cylinder internal combustion engine on the ES300h and with the 300h being a relatively large/heavy vehicle, you are more likely to get into situations where you need to be forcing the engine into a lower gear to avoid engine knocking, and, again, punching the accelerator when the engine starts laboring will force the transmission to down shift. Also note that, if you are driving in Eco mode, the transmission is programmed to try to stay in a higher gear as often as possible, and that will mean that you are even more likely to have situations where the engine starts to labor and knock while climbing a hill or accelerating while in a gear that is too high to get the job done.

Even with my ES350, which has a lot more torque and horsepower than the ES300h, if I'm driving in Eco mode and if I'm climbing a very steep hill, there are times when the programming of the transmission shift points is such that the transmission will want to stay in a higher gear than what it really needs, and I need to punch the accelerator to force it to down shift so that the engine will get its job done without laboring.

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.

steig

My 13 ES 300h also has this knock. Tried different gas, but did not help.

Lexusxoxo

Oh wow! I have not noticed a knock with my 13 ES300h.
Will keep my ear open for it. Hope this isn't a wide spread problem.

jim256

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.

lesz

I doubt that it is a problem at all. Four cylinder engines have to rev at higher RPMs than 6 or 8 cylinder engines, and, to run properly, they need to downshift more frequently than do 6 or 8 cylinder engines. In an effort to maximize fuel economy, I'm confident that Lexus/Toyota has designed the transmission to get to and stay in a higher gear as much of the time as possible, but, when accelerating or when climbing a hill, lower gearing is needed for the engine to run properly, and that sometimes requires the driver, as I said in my earlier post, to punch the accelerator and force the transmission to downshift.

I could force any any engine, even a V8 and even when premium fuel is used, to labor and knock by manually operating the transmission and keeping it in top gear while the vehicle is trying to climb a steep hill, but, again, this becomes even more of an issue with relatively small 4 cylinder engines powering relatively large vehicles. The issue is not likely to be one of being a problem with vehicle. It is more likely an issue of driving style. While it is commendable in many ways to drive in a conservative manner and one that attempts to maximize fuel economy and while that generally means getting the transmission to top gear and keeping it there as much as possible, there are times, especially with a 4 cylinder engine, when lower gearing is needed to allow the engine to function optimally, and that means forcing the engine to downshift when that is what is needed.

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.

lesz

Yes, I understand that the ES300h has a CVT, the general principle of gearing applies in the same way that it does for a conventional transmission, and there are going to be times, especially with a smaller engine, when lower gearing is called for than what the transmission is programmed to yield. And, when that happens, what is called for is input from the driver, via the accelerator, to change the gearing.

As I said in my post above, I think that there is a high probability that the reason why some are saying that there is a problem and why others are not seeing the same problem has to do with differences in driving style. Further, I think that there is a good chance that, if you took someone who thinks there is a problem and someone who does not see the problem and had them switch vehicles, the person who thinks there is a problem would be experiencing the same problem with the other person's vehicle, and the person who is not seeing a problem would not see a problem with the other person's vehicle, either.

LexBob2

This is a diagnosis probably best left to the technicians.

atoyota

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.

Arty101

Costco claims their gas is "top tier". That said, I suspect atyoyota may have something there. We're changing out from winter to summer gasoline, and octane can be affected by the ethanol used between the two. Try premium gas for a tankful and see if it persist. I'd also use a separate additive such as Chevron's Techron in that tankful. If that doesn't help, bring it back to dealer. Good luck.

bc6152

You should not be hearing pinging with Costco gas or any other name brand 87 octane gas.

FYI - Knocking in spark-ignition internal combustion engines occurs when combustion of the air/fuel mixture in the cylinder starts off correctly in response to ignition by the spark plug, but one or more pockets of air/fuel mixture explode outside the envelope of the normal combustion front.

jollick

I have never heard a knock in my 2013 ES300h with 12,000 miles on it going up hills or otherwise. I always use Kroger Regular. I also had an HS 250h from 2010 and never heard an engine knock.

LexBob2

Yes, Costco is listed as a Top Tier retailer. BP wasn't on the list until a few months ago. I've always felt that TT is as much about marketing as it is about gas quality/additives.

ryoo1257

We'll see, I picked up the car today and they put in 91 octane...why they did that I don't know,,,, their manual states 87.