2012 v6 at DCSB engine knocking @ 1500 rpm

Has anyone installed a supercharger yet on a 2012? Does it still make the noise?

 

Hi All, I'm new to this site and actually this is my first post. I have a 2012 4.0 4x2 DCSB SR5. As much as I love my Taco, this "1500 rpm engine knock" is driving me crazy! I've gone through a "dealer fix", arbitration, ND Iridium plugs and still have engine knock. Toyota Customer Experience says the Field Engineers call it normal! There's no way this engine knock could be normal. Anybody have any suggestions?

 

My 2012 dclb v6 has this same pinging issues as well. Have not had time to talked to dealer yet. Thanks to those who had tried the fixes.

 

Hi all,

Wanted to report similar issue for me:

2011 Tacoma 4.0L 36,000 Miles (started happening this summer)

I notice it the most or is reproduced when cruising along at low RPM with A/C on, usually triggered by slight hill or uphill terrain and trying to maintain speed. The engine creates an almost gurgle-y type sound with some knocking type noises. Very similar to the video posted earlier in this thread.

I was really disappointed when this started because I've been babying this truck since I bought it. I thought I must have gotten on it too hard at one point and did some damage to the engine or something crazy. Either way I'm eagerly awaiting the potential that Toyota will issue a fix or another more solid answer will come about.

This truck is way too new to be making such a nasty noise.

 

I always use Super (93 octane around here, 91 in other places) and have never had knocking problems either in my '09 or my '12. Recently a buddy of mine drove my truck and filled it with Regular Unleaded. I got on the gas hard with a heavy load, and it knocked pretty badly -- he was in the back seat, so I asked him and he confirmed he put cheap gas in it.

I have done tests and always get better mileage with Super, enough to where the cost difference evens out a little. The fact that it will most likely keep the valves and injectors cleaner completely evens it out, in my view. Don't be cheap, use Premium. It may take a couple tanks to clear things out.

Maybe a reflash will help the timing.

 

The pinging does indeed stop when I tried 93 octane gas, but the manual specifies 87. Why should I have to use 93? I commute 80 miles per day and in this day and age money is tight. A new vehicle should not have this type of problem when run on the specified octane gas. If I new this truck would "require" premium I probably would not have bought it. It will ping on any brand 87 gas. In my opinion, it seems Toyota refuses to fix the problem or doesn't have a fix.

 

Automatic

 

ETA:

What year did Toyota go from catalytic converters as a separate piece after the header to the combined unit found in the '11 and '12? The '05-'06 FSM shows separate units. JTFC, that's almost as stupid as Chrysler going with the exh. manifold being a part of the head casting in their newer Pentastar motors. Anyway...

I did a little experiment last night. I stopped the truck next to a large concrete retaining wall (8' high or so), about 4 feet from the wall and parallel to it.

I goosed the throttle (in neutral, 4.0/AT) and heard the typical Tacoma 'tick'. Next I got on the throttle and kept the RPM's at the magical 1300-1500 RPM range. The noise I heard in neutral was identical to the noise heard under load (had my window down, radio off, so I could hear).

I'm starting to think this is related to the 'tick' we're all familiar with and partly represents some variation in manufacturing tolerances or some running change in the 4.0L between early 2011 and the start of the 2013 MY.

I'm not overly concerned about VVT-i here and its relationship to the elimination of the EGR system. EGR generally comes into play (in cars with an EGR setup) at cruising speeds and lowers combustion chambers (to reduce NOx formation). EGR-type effects of VVT-i should not (can't say they 'don't', but they should not...) come into play during acceleration, which is where people seem to notice the knock/ping noise. Besides, if it did, by keeping more exhaust in the cylinder, your cylinder temps should be cooler, which I *think* (if the books made sense to me) should tend to eliminate spark knock/ping/detonation.

I've watched the "IGN" (timing) readout on my ScanGauge II during high gear (usually in 4th+Lockup or 5th+Lockup). When cruising easy at 40MPH with 5th locked up, timing reads out usually between 27 and 32 degrees. That's some pretty good advance (running Chevron or Shell 91 octane). When I get on the gas lightly, timing retards to somewhere around 20-22 degrees. If I have to get on it hard, i.e. to pass or go up a grade, timing will drop back momentarily to the 15-17 degree range, and sometimes as low as 13. From there the computers have a decision to make - downshift or keep the gear. With a downshift, timing advances back a bit (into the mid-20's), without (usually when throttle pressure is lighter) I have watched timing retard all the way to 3-5 degrees.

So the million dollar question in my mind is this - is the computer retarding the timing based on:

1. predefined maps in the ECU? or,

2. those same maps + a variation based on input from the knock
sensors?

Is there a way to tell (without an o-silly-scope and hacking up my ECU harness) what the knock sensor is telling the ECU? Let me condition that - I know the techstream (the real ones) can tell you several knock parameters. Is there a way to grab that via CAN-OBDII with a ScanGauge or some similar tool?

If I had a project truck and no stupid smog laws, I'd MegaSquirt this mofo and be done with it.

 

A couple of events I want to report. This past week we had a heat wave here in southern California and I heard the pinging sound again after not hearing for a while after I changed over to premium. I believe the high heat, the A/C at full blast and in traffic brought back the pinging sound. The second event was when I was coming home late Saturday morning after a morning surf session in my brother's 2012 V6 Jeep Wrangler. I heard the exact same sound only more pronounced. He said that the jeep dealer told him it was normal.

 

I understand your viewpoint, but since the US insists on continuing to sell crap gas, car manufacturers will try to tune their engines to run on it and put that 87 number in their manuals because that is what is available at the pump. The rest of the world has moved on, and "regular" gas is typically 90 octane.

A lawnmower with a low compression ratio will run fine on 87, but most newer motors have a higher compression ratio. I think the 4.0 we have is around 10:1 or something. With the heat this time of year, the air/fuel mixture in the cylinder is more likely to reach that magic temperature for pre-ignition. It's science.

The only way to overcome the ping is to retard the timing, which reduces power output and economy. I agree that Toyota should do a better job of tuning the timing properly to avoid pinging. But, that reduces your fuel economy, and there's nothing unique about the Tacoma -- no manufacturer is immune to science.

I get that Super is more expensive and the manual says 87. But it will run better and cleaner on Super, and doesn't really cost that much more.

Say 15 gallons of Premium costs you $5 more than Regular. I get 20 mpg on Premium, 19 mpg on Regular (I have done tests, and this is about right for my driving). You need almost a gallon more of Regular to go the same distance as on Premium. Subtract $3.20 from $5.00, you are down to $1.80 difference per 15 gallons. Or somewhere close. Not that big of a deal.

 

You do understand that 87 has a higher heat output then 93 right? That kind of makes it a better choice for economy.

 

I've been noticing people complaining about this in other make and models of cars (from Nissan Frontiers to Mazda CX-5's) as I have scoured the internet. It's starting to sound like something else is going on with either the push for fuel economy, gasoline formulation, or some other combination of things related to fuel, efficiency and engine design.

Here's what your 4.0 1GR-FE has in common with the 3.6L Pentastar in that Jeep:

1. Aluminum block (Miss my 5VZ-FE a LOT, now).

2. Variable valve timing.

3. Delete of the EGR system due to #2, above. Valve timing now is used
to sufficiently "pollute" the cylinder to lower combustion temps on both
motors.

4. Aggressive fuel efficiency tuning.

5. Both are running on California-formulated summer gasoline. (junk)*

6. Some of those Pentastars tick just like the 1GR-FE:

http://www.youtube.com/watch?v=4Pl-7zl0RsI

A guess/question: The Jeep has a 5 speed auto slushbox with 'lifetime' fluid - did they (Chrysler) source an AISIN unit? Jeeps have used AISIN gearboxes in the past, and I think even used a variant of the A340 from previous Tacomas.

Also, Google on the phrase "2012 Wrangler pinging". It's....enlightening. (No swipe at Jeepers, I used to be a Jeeper in my younger days).

Something's up and it isn't good.

 

My truck has less than 200 miles on it and makes the same gurgly/ticking noise.

 

Beavis0076, right, thanks, makes sense. I think I was just over paranoid because I had this problem and didn't know it existed for others.

Anyway, quick update from me, I've been running nothing but 87 per manual recommendation since I purchased the truck. I just this week switched to try the 93 octane and it has not made the noise under low RPM load since. It only took that one tank for me. Noticed an improvement right away.

Though not the fix I am hoping for. It makes me feel a little better it's running smooth with 93 for now. Also, I have noticed a slight improvement in gas mileage (running ScanGauge II) though I doubt it will offset the cost fully. We'll see...

 

Interesting. I'm still on the first tank that the dealership filled it up with....I'm betting that it's not 91/93 octane, haha.

I'll have to fill mine up with the highest octane I can find to see if it goes away. I'm at about 1/4 of a tank, should I just go ahead and fill her up to see if it goes away?

 

So we should be using gas without any ethanol added? Every station I've ever stopped at adds 10% ethanol to the fuel. How the hell do you find fuel without it?

 

We can run E-85. Just need larger injectors and larger fuel pump, and a way of controlling that...

 

I might just wait. Otherwise, you'll have a tank full of more expensive gas and a test case that isn't 100%. (if you are at all questioning whether you want to spend for the 91/93 regularly) But if that doesn't bother you, I can't imagine it would hurt. Only improve the potential things would smooth out.

 

Just looked...not a single one within 40 miles. Just my luck.

 

Oh lord, I think I have the ping now. i took my truck in for 15K mile maintenance and a day later while I was driving up a slight incline I heard what sounded like a loose part bouncing around in the engine. At first I thought they left a tool under the hood or didn't tighten something up but I checked and all looked normal.

The conditions were perfect for ping. Hot as hell out, AC on, low RPMs driving slightly uphill. I'm going to try 91 Octane and see if it goes away. I've used nothing but 87 since the first fill up around 15 thousand miles ago.