My 07 TCH had this very same rattle in it... I fought it with 92 octane sometimes, but the increase in fuel cost did not justify it... Finally gave in and wrote it off like I did the squeak in the console and the moaning of the rear brakes..

 

Almost a year later and no definitive solution yet? My 07 has the EXACT same issues as the post before me, down to the rear brakes moaning when I go slowly in reverse. My 07 has a little over 135K on it. I want to keep this thing a few more years but the rattling under the hood is driving me crazy. And no codes are thrown either which is even more frustrating. I've replaced the 12v battery so I've had it disconnected for more than 5 minutes and that did nothing to fix the problem. I tried using premium grade fuel for about a month a while back but that didn't really do anything. I drive up a parking garage at work every morning so I get to enjoy the sounds heavy rattling coming from my car every morning. And like someone else posted, I either hit the gas to make it go away or, on special days, I have to let off completely and then apply gas again to make the sound go away.

 

Carlos,

Take your car somewhere that can reset the computer (ECU) to factory tune. I think you will find your problem will disappear. By giving the car more gas or backing off and then getting back on the throttle again is a dead giveaway for the issue you have. The ECU has adapted to your driving and is running too lean on slight acceleration or slight load conditions (going up a parking ramp at slow speeds).

 

Yea.... I remember the parking garages being the worst. Going up the inclines into the garage you can really hear it echoing off the wall if you have a window down. It sounds like the engine is coming apart! And "gunning it" (pedal to the floor) makes it go away completely!

My problem came back about 4 months after the computer reset? For whatever reason.

My car is now at 164,000 miles.

In my case, running 93 octane does cure the problem. But, I am not willing to pay for it every tank. I noticed that if I run 93 octane every other tank seems to work in my case. More than 2 tanks of 87 octane and the noise starts again.

I have read some threads elsewhere about oil consumption problems and a piston "re-design". Someone actually had their engine rebuilt with the newer pistons to cure an oil consumption problem. I wonder if the problems are related?

I have noticed that when I can keep the car from pinging that the oil consumption does STOP completely. When the noise is there often I can count on topping off the oil once a week up to a full quart over 7500 miles.

 

Thanks for all the replies. I gave up on fixing the issue. Toyota doesn't seem to know what to make of it and the car has 65k on it now. I usually just use Chevron 87 octane E10 and mostly doesn't happen all that much. I live in SouthWest Florida with zero hills and usually get 36 MPG every tank driving her a little still.

 

As long as the spark plugs have been replaced with the oem plugs for you car. Next I would make sure i'm using a top tier regular gasoline. I would buy a bottle of techron and run a bottle in 3 full tanks of gas to clean any deposits out of the engine.

I knew a few that did this on non hybrid cars and it worked. In the old days they would pour a pepsi bottle size of water down each side of the carb while revving a heated up engine to about 3500 rpm while in park. This quickly steam cleans the pistons, rings and valves. This was back when they first introduced unleaded gas and it left lots of deposits in the combustion chamber especially on the piston tops.

Actually this pinging problem when accelerating sounds very similar to the problem we had back in the late 70's.

I would warn against using any water down the intake in today's high tech engines. Now we have sensors that may be damaged. The water carb treatment we did included then having to replace the spark plugs and changing the oil as the water would get into it and could damage a crank bearing. Some I heard replaced the water by using brake fluid or transmission fluid.

Techron can clean the engine just as well including the fuel injectors. If you try it, be sure to read the instructions and use it at the gas station were you can pour it in then fill your tank to mix it in thoroughly.

All top tier gasoline's use techron labs or a very similar additive in every gallon of gas.

watch the video below then click Retailers at the top of the page.

toptiergas.com/

type in your zip code below and search your area for a low price top tier gasoline station. It's best to locate a consistently low priced top tier station near a small no-name discount mom and pop station.

gasbuddy.com/

 

I should mention when I had my '07 TCH I did get a bad tank of gas at a Texaco station not long after they had replaced their underground tanks. One night climbing a overpass with the windows cracked open my wife heard pinging on her side reflecting off the concrete wall on her side of the car. I added a bottle of techron once the tank was half full and I refilled it then with Chevron. I took the 3 refills each with techron to clear it up. I used Chevron for a year then they opened a new top tier phillips 66 station with low prices only a block from a no-name discount station. I been using phillips 66 after that including a year or so of diving the new '12 TCH with no problems.

 

Yea... That is total BS.... It is NOT the fuel. It is a sensor, computer, or other related problem. I had a similar problem on an old truck I used to own. It turned out to be a bad Knock Sensor (there was a couple of them).

Techron and or TOP TIER GAS DOES NOT DO ANYTHING FOR THIS PROBLEM (for the last time). I have been running nothing but that for so long I cannot remember now. I am probably keeping the makers of Techron in business (@ over 165,000 miles).

My best guess is that it is a software and or hardware related issue. IE: components working properly and talking to software... Then the components quit talking to the software, computer tries to compensate and the failure occurs. The result is the "Pinging".

The problem is simple and just a question of timing "IF" all the sensors are working correctly.

The **** car is pretty much flawless otherwise... Screw it!

 

So sorry, I was telling my experience with pinging on my car and how I cured it. I'm older and keep forgetting these hybrids have 10 or so sensors that could possibly give trouble.

 

No need to be sorry.... I realize after re-reading my post, it may have sounded a little "hostile". That was/is not the intent. Just frustration over the whole issue that many of us have learned to live with. I am sorry if it came across the wrong way.

To the others that are suffering with this problem, "I feel your pain". My last tank was 93 Chevron. The tank I am on now is Chevron 87 and it is close to empty. Today on the way home from work it happened when I had the windows down, cruising at about 36 MPH with the ICE on. Sounded like a 75 Oldsmobile... So, its obviously getting worse again.

Toyota says all sensors are fine and no codes are stored. I would like to see some timing #'s on the car while it is moving and while this is happening. It has got to be way off? Or maybe a sensor is failing at a certain Temp., RPM, etc...

It still continues to be a great car overall regardless! We are driving a ton of miles again due to our job. This week we drove 895 miles. Last week 687 miles. It is really nice to have a car that I know we can rely on!