2012 v6 at DCSB engine knocking @ 1500 rpm

Just wanted to share the symptoms on my 2012 with 8,000 miles . The engine makes a wierd knocking sound right at 1500 rpm , but I don't notice it unless I'm going up a hill at around 40 mph when the engine shifts and drops to the low rpm that's when I can hear the sound . But if I'm at a comlpete stop and rev up the rpm it sounds completely normal. I haven't had time To take it in to the dealer yet but will soon. Should I be concern or is this normal. This is my fist Tacoma.. Thanks!!

 

Try it with different gas.

I know the tranny likes to upshift a bit too much. I guess it's trying to save gas but I frequently don't agree with it so I slap the shifter quite a bit.

 

It's running on reg fuel haven't tried 89/91 octane .

 

not my tacoma, but my rav4 does the same thing when the engine is cold. it does not knock when revving in idle. but knocks when driving / engine under load when the engine is cold. dealer keeps saying it's normal but i think it's the timing chain tensioner.

 

I'll chime in here to post my experiences on my 2011 which now has 11,000 miles. I had the first oil changed by the dealer for 'free', in which I carried in my own Mobil1 5w-30 full synthetic at 5000. I would say about 7500 I noticed that the ticking, which is normal, became more pronounced.

Since that 'free' oil change was a complete waste of my time (I live in a heavily populated area of NJ) and took 2.5 hours to do on a Saturday, I've decided to nix the 'free' oil changes and do it myself like I normally would on my vehicles.

After reading through some notes I found on TW on the quantity to use on the V6, I started off with exactly 4 quarts of oil, ran the engine a bit, checked the stick, then added the extra 1/4 until the level was right in the middle. It took a full 5 quarts, rather than the standard 5.5 quarts. I even waited a few days for the oil to visibly darken, then doubled checked the oil level to confirm the level.

What I noticed immediated was the ticking noise was significantly reduced and muffled. It makes wonder me if, when I had the oil changed at 5000 miles, the dealership even used the 5 quarts of Mobil1 I provided...or even if they added the correct level of oil as well as changing the filter. Shame on me for not checking the oil afterwards or at all during that interval.

In terms of knocking noise, I haven't noticed any pre-detonations or anything causing a misfire. I haven't noticed any physical knocking sounds either. I do experience pinging noise every now and then, and its mostly related to the high ambient temperatures + increased humidity levels + the fact that I'm only running 87 octane + gasoline quality/age.

 

I'll try running premium this weekend since I'll be going out of town on a 600 mile trip . So hopefully the noise is reduced or eliminated. In terms of oil and gas do u guys run premium? I know theres a big debate on that.. And also would it big wise to switch over to full synthetic ? Thanks for the feedback!

 

Many users report better mpgs with 91, enough that it can offset the higher per-gallon price.

The ticking sound is inherent to the valvetrain design. It doesn't affect longevity. Not worth switching to syn oil just in hopes of quieting it down.

 

So I've been through 3 tanks running 91 and I must say the knocking sound is
Gone . As far as the gas mileage didn't notice much difference, but the engine does idle alot more nicely!

 

they like 91, i say this with 87 in my tank and since my trucks a manual i can make it ping incredibly bad when i drive it "wrong". surprized they even got it rated to run 87 with a 10:1 compression ratio.

still nothing like my 92 truck did though. that thing really pinged on 87. never blew up

 

I ran my gas tank further down this week to where the needle is in between a quarter and empty, then filled up with 93 last night. I've been using 87 all summer, and i finally got to 21.1 mpg! Anyway, this morning when I went to the dumps, I drove up the hill of my neighborhood and noticed immediately the truck feeling like it was pulling itself with the pedal only about an eighth to a quarter of the way. That subtle pinging noise on the low end wasn't there either. Ill see what happens with the mpgs this week if I can manage to drive normal.

93 definitely makes the 4.0 engine run and perform better. If you want a cost effective engine mod, use 93 instead of 87 for a few dollars more.

 

Ive notice the same thing with my '11 4.0. I was hearing what sounded like almost predetonation, but only at slow speeds(below 35mph), took it to the dealer, they told it was normal, part of the VVTI. I started running 93 octane and most of the noise is gone, which kinda negates the VVTI theory.

 

Mine was pinging pretty bad today...under 35 mph, slight incline, 1500 rpms, A/C on. Loudest I have heard it to date. Been running 87 since day one, just hit 6300 miles. For the technical guys...is this something that can cause damage over time?

 

its not a good thing, but no doubt your motor is built to withstand what you can hear, knock sensor takes care of it and retards timing to keep it minimal.

if you think about it, its your air-fuel mixture exploding while its still being squished by the piston(s) during their up-travel. tough on the entire bottom end

 

If you are near sea-level you can get away with low octane, however those of you at higher elevations that rob you of power, I would recommend premium gas only. Especially if you are going on a trip to really high elevation. You need to run through several tanks of premium before you might hear a noise difference, premium will eventually clean everything out.

Lifter tick, valve gunk, noisy spark plugs, really the only thing you can do is run a heavier oil, and better gas or change your plugs.

Some engines are more noisy then others. Let's be honest, there really is nothing service can do for you, and if your motor is not throwing misfire codes, or other codes related to your heads, no way they are going to pull your heads and rebuild them.

Just live with it or trade it in, really only options, spending time trying to convince Toyota or any other car company that they should re-build your motor is a uphill battle, especially with no codes.

Have a shop pull codes or log for misfires, this could give you some ammo. But misfires are almost always solved by better gas and new plugs.

 

False again. Higher the altitude the lower the octane required. There are limits to how far you can advance the ignition with high octane, but since the high altitude air is thinner it simply won't help.

 

x2

 

I would say generally this is true, however, we just make way more power at elevation using race gas... Verifiable results every day.

We need race gas to make similar power to pump gas at sea-level.

 

So much for the knock sensor. It has no business knocking it was designed to run on 87. Take it back and make them fix it and be sure you tell them it's "knocking" and get a copy in case it's not spark knock. I refuse to waste money on 91 I can mat mine in 6th at 30 mph and it does not knock and it doesn't knock towing my camper up hill either. The tappets are mechanical they are noisy just like any other engine that has machanical tappets but loading them won't make them any noisier.

 

I think maybe some folks are mistaking the "Taco Tick" [VVT-I rattle noise] as pinging. At higher revs like 1500RPM it sound a lot like a faint pinging.

 

I would suggest using SHELL or CHEVRON if you can, using cheap gas will cause knocking period.

I get premium gas at Costco for the price of regular at most gas stations.