2018 cylinder issue suggestions please

English version. I don't see how a little gear hunting relates to his valve problem.

 

I'm definitely doing one and possibly the other.

I'm not sure why you are asking, you own one, how don't you know?

Ha! The English to french back to English is close but not perfect

 

If he is not sarcastic saying that then he is probably one of those dudes that own a 1st gen, cuz it’s the best right.

3rd gen is rock solid, just like any gen Tacoma.

 

My truck has been great, so are my buddies and other hundred of thousands happy 3rd gen owners.

 

Hopefully mr bassman is not one of those salty 1st gen owners. We already have enough of these guys here.

 

Yeah, I still have my first gen. Sold the third gen for not meeting expectations a couple years ago.

 

I see. That’s too bad man.

3rd gen exceeded my expectations, I’m a happy camper. I tow, wheel, carry loads and take road trips. Awesome machine. If back seats had 6” more legroom, this thing would be perfect for me.

I bought it without test driving too.

 

Anyone figure out what caused it to burn 4 valves in the same cylinder to begin with ? I deal with burnt valves quite often in aircraft engines, but it’s always exhaust. I guess with variable timing cams and the Atkinson timing blowing air back into the intake, all sorts of things could happen

 

I'd like to know that too and is this usually on #3 cylinder?
I hope OP gets his truck back and likes it.

 

this is my last conversation with the dealer this morning. I hope that a “top end” engine repair is “minor”. I love my truck. I guess I’m stressing from lack of auto mechanical knowledge. Construction is more where I am.

#3 cylinder
4 burnt valves is from in my case)
A: mechanical defect
B: customer abuse ( occasional redline?)
You should be able to stomp on it to get on the freeway and 1st gear or 2 does climb near 6k but as far as I know it can’t or has never gone past 5,900

 

I can’t imagine customer abuse, especially if it has auto trans. The trans being another level the manufacturer can use to limit what the driver can subject it to. If occasional redline caused this, they put the damn red line in the wrong place. And ……usually #3 cylinder? How usual is this ?
I’m just curious. I don’t have this engine, but love a groovy mystery.

 

Same engine in the Camry redlines at like 7k rpm, definitely not abuse on your part. Just luck of the draw…

 

OP- it’s not abuse on your part lol. You’re fine. It’s just a bad luck type of deal. Don’t stress. Let them fix it, enjoy the rental (and if they didn’t give you a truck as a rental, ask for one, they usually don’t have a problem with providing an equivalent vehicle) and let them do their thing. You just got unlucky. The dealer seems to be taking care of you, so let it ride.

 

That's what I asked earlier. Never seen a burned intake valve and don't think the Atkinson cycle would cause it. It's blowing "cold" air back over the intake valve not hot exhaust gases. Purely a guess on my part but I'm thinking something went wrong in the initial install of the valve guides. Eventually causing the valves to hang open and burning the exhaust valves. Toyota probably says to replace all the valves/guides on that cylinder to fix the issue.

Sure Toyota knows the exact cause of this but isn't telling.

 

If I understand correctly, Atkinson cycle is when an intake valve is held open a bit during a compression stroke under light loads. Don’t think that air is cold.

 

That's exactly how it works. That's why I said "cold" as in its still likely hotter than ambient (I'd guess not that much) but much cooler than exhaust gases. That's why you typically only see exhaust valves burn because they get much hotter air passing over them than intake valves.

 

I’m following hoping to see what happened. It’s amazing how many vehicles these days from manufactures that have been in business a century or more are experiencing failures. Hope this incident is one of those. Been having some late model gm issues myself. Ordered a new 2.7 hilux engine that’s supposed to arrive this month in a new Tacoma. Lived in Mexico a few years and we couldn’t kill the companies hilux pickups.
As far as valve problems, I deal with it quite often in aircraft engines. Pulling a 540 lycoming engine now that had a valve stick from excessive guide wear. Bent a pushrod, broke a lifter body, and damaged crank case. Engine shop quoted $46,000. Big continental engines often get lead deposits that hold valves off the seat and then they burn.