What’s the problem? Say WHAT?!

I got my truck back from the dealership after a full 2-week warranty repair. I’m good enough with engines to understand the concepts, and I can work on vehicles 1990’s or earlier, but what the mechanic described the issue, I was stunned that this could happen to a truck 1.5 years old. His report was that valve #1 was not fully seating, and it was causing some carbon build-up (since the gas wasn’t completely consumed). They needed to replace the head, and that valve. Has anyone else had something similar on their ‘22?

 

be happy you have a warranty - remember to ask for an "extended" warranty now that they have acknowledged the issue/problem/solution. No guarantees their work won't result in the same or other issues down the road. GL.

 

Not on my my taco, but I had it happen with a brand new 2018 Jeep Grand Cherokee with 200 miles on it. The head had to be replaced. Ends up the valve channel wasn't bored to the correct spec on the #1 cylinder and the valve kept getting stuck open when it expanded in the channel.

 

There are such things as manufacturing and assembly defects. Humans are not perfect.

 

I’ve never heard of this, I’d guess an isolated case,,, they do happen to any and everything.

 

Not an isolated case.
It’s a known issue that “can”, but doesn’t always happen on the 3.5 engine.
It’s been posted about, and happened to other members.
Unfortunately, most of the threads are thrown off course by people arguing about what engine is better.

 

I’m glad that it’s been talked about. Hopefully, the problem’s solved on my end, but I did want to share it, just in case.

 

speak for urself

 

Out of curiosity, what are the symptoms that led to this diagnosis?

 

That's what warranty is for, manufacturing defects. Glad they took care of it for you.

 

I can’t speak for OP, but it’s usually a misfire condition.

 

It was a “Check engine” light, and I was quick to bring it in because I wanted to maintain the warranty agreement. The mechanic said there were 4 codes, he doubted it was all 4, but he would have to evaluate each possibility to figure out which one was the real culprit. Aside from the light, I couldn’t tell from performance alone.

 

It’s unlikely that missing a tire rotation and/or and oil change is going to cause problems with a warranty claim.

 

So did he disassemble it or is he just supposing?

If the ACIS flap fails, it can shit a little bushing into intake 1
https://www.tacomaworld.com/threads...fks-second-update.793953/page-2#post-28453741

 

Find out with the codes are, more information for the forum to use. If it’s one of the “P11..” codes, then you have a bad valve or cylinder head valve seat, which throws off the air-fuel ratio and is why the code gets reported. To have 4 codes is odd.

things happen, and it sucks, but what concerns me is this failure has popped up numerous times. Obviously that’s small potatoes in the grand scheme of all Tacomas, but that’s like the only mechanical defect on this engine…so something must happen to make some of them more prone to have the problem. The good thing is statistically, it’s very rare but it sucks if it happens to you esp out of warranty.

 

He took it apart.

 

I’m with you, and agree; however, this light came on, and neither of those services were due.

 

We have seen a handful of posts on TW 3rd gen with similar valve or valve-train related issues. As mentioned, it's a manufacturing defect. Uncommon, but they do happen.

 

My 2022 tacoma the driver side cylinder head and valve cover started leaking oil at 4k miles. Engineer diagnosed it as a defect of the cylinder head. They pulled the engine and replaced the head and valve cover. I traded it in while it was still getting worked on and got a 2023 identical truck. Toyota gave me $1500 towards the price of the new truck. 2400 miles on my 2023 model and no signs of oil leaks