2012 v6 at DCSB engine knocking @ 1500 rpm

I saw the Survey Monkey thing and responded, but we can't see the results. What are the results so far?

 

SurveyMonkey only lets you ask 10 questions with the freebie account. There were 4 or 5 other questions I wanted to ask, but couldn't.

 

You should've seen the 2005 owner's manual - it explicitly recommended 91 for best performance and fuel economy. The engine hasn't really changed since then, but the politics have.

 

So far there are only 8 responses. I need to get this posted to other Toyota-oriented boards, I just haven't had time to hit them all. Plus as a n00b to some of them, this would go over badly as my #1 post. That said...

Model Year: (6) 2012, (2) 2013
@ XXXX mi. = when ping appeared/was noticed.

2013 @ 11,000 mi., high octane help = no
2012 @ 5000 mi., high octane help = no
2012 @ 3500 mi., high octane help = yes (w/ 93)
2012 @ 16,000 mi., high octane help = yes (w/93)
2012 @ 2500 mi., high octane help = no
2012 @ 15,000 mi., high octane help = yes (w/ 93)
2012 - No ping
2012 - No ping
[2012 @ 11,500 mi., high octane help = no (max available = 91 & using)]

The sample is statistically too small to say much, but it suggests strong support for running high octane as others have suggested. I haven't taken my own survey yet, so my data is last in "[]". Could be 2 points on the AKI makes the difference, and I don't have access to that. It's either 91 at prevailing California prices, or $7.94/gal at the only station within 40 miles of me for 100 Octane Sunoco.

I don't think Nevada has 93 anywhere, but if I see it, I'll tank up on it and put 5 gallons in my jerry can and see what happens (I'll save the 5 for when I'm back in CA, after I run the tank down).

If anyone wants to share the link to the survey, feel free. I'm hoping for 20-30 responses, at least. Looks bleak. Like everything else. :-/

Nite folks!

 

My manual only says improved performance use 91 or higher......didn't say anything about best fuel economy.

 

Semantics.

If you have baseline X using gas A, and you * improve* on baseline X using gas B, and those are your only choices - then obviously gas B gives you the best performance. Let's not lose sight of the big picture by picking apart the semantics of it all.

 

Not just semantics, Toyota didn't say improved mpg, that just your assumption. My 2005 owners manual has 15 suggestions for better mpg, but no mention of higher octane.

I'm speaking to mpg, not best vs improved.

 

If only 91 is available and doesn't solve your ping after running a couple tanks through, you can get octane boost additives. I wouldn't want to have to do that all the time, but it would be good just for a test. Gumout, STP, O'Reilly even has their own generic.

 

No, that's where "I'll pay more for gas" crosses the line to "This is bullshit." (the buying additives part)

Besides, I think I mentioned in a post yesterday that I 'mixed' to 93 yesterday morning. If not... I had ~12 gallons of 91 left in the tank, and I added 3 1/2 gallons of 100 octane pump gas, and the problem persists.

I used this calculator:

http://www.wallaceracing.com/octane-mix-calc.php

Those quantities get you to a 93 octane result. Pinged away all day yesterday.

 

2011 manual, "87 or higher" what they are saying don't use 85. Has any one stopped to think maybe this is not spark knock? Why does this engine have a knock sensor? Why does it not retard the timing if a knock is detected? How come mine does not ping even when I mat it in 6th at 30 mph running 87 or pulling my camper up a 13% grade? How come many show no improvements in either power, or fuel economy with 91? I buy good beer because I like it but cheap beer has the same effect.

 

I noticed this in my 2010 around 60k miles I have always ran 87 without ethanol. I tried going up to 89 with no ethanol but the weather is starting to cool down and it does not seem as noticeable. I will try checking this some more and try some 91 with no ethanol.

 

Wouldn't that be funny, if it ended up being something like that?

 

It sounds to me like classic engine knock, pinging, detonation, spark knock, etc.

 

Again why doesn't the knock sensor "fix" it? They have all ways done a good job in the past it's not a new ideal the old 3L had them they worked.

 

After countless miles of testing, my input on this issue is spark knock. It's all because how the ecu is programmed to "save gas" the knocking usually happens on hotter then average days. Under a good load on the gas pedal in a higher gear at low speeds. It seems to be a common problem in other Toyota motors also.

87 gas under normal use is fine, once it gets hot outside it starts knocking/pinging
91 helps out with the pinging but once it gets hotter then hell outside it starts knocking againg under load in high gear.

Solutions? Bitch to Toyota and maybe the engineers can reprogram the ecu.

I never notice this issue on the 2011 and below tacoma v6 engines. Major difference between the 2011 and below vs 2012 and up is the smog emissions stuff and probably different ecu programming

 

There are many others complaining of noise on TW in years at or below 2011. The only thing that was changed was EPA CO2 emissions and that was industry wide. Now CO2 is a good indicator of engine efficiency the higher the better now who wouldn't want that? If the cylinder temps were higher (better chance of speak knock) the Nox would be high no one wants that because it will affect the CO2 output and the air we breathe there by reducing the efficiency of the engine this generally occurs at or above 2500*. There is a finite amount of chemistry in the burning of gasoline each product effects the other one’s high the other must be low and vice versa. So if Toyota’s mapping is incorrect it means their trucks would not meet EPA’s standards and it’s doubtful they would get away with that for very long. Unfortunately I can’t comment on the noise because no matter how hard I try mine will not spark knock even burning 87 and 10% ethanol. It is a noisy engine there are a lot of parts going around in there and the headers seem to be resonate. If spark knock is occurring in some engines it should be easily duplicated at a standstill by stalling the converter for those with an automatic. The knock sensors do a pretty good job of reducing spark knock and have for years so why wouldn’t they now?

 

My experience is the same as yours, except I have the small 2.7 with a manual transmission. And even though I don't have any knocking issues even though my work truck is always fully loaded with tools and materials, I could hazard a wild guess...

When I see how so many trucks are set up, with these huge heavy gigantic diameter off road tires and rims, and all those heavy steel plate bumpers, guards, bars, skids, and winches, and trucks equipped with every kind of powered option you could possibly imaginable...

...It would surprise me if the poor overloaded engines didn't knock.

 

My 2012 4.0 auto is completely stock and still pings like crazy.

 

I'm sure that opinion couldn't possibly apply to everyone. Had you tried diagnosing the knock sensors on your engine?

 

Wouldn't Toyota have done that? I brought it in twice already, to 2 different Toyota dealers for the pinging. They did confirm the pinging on both occasions.