P11EC00 error code update

Based upon research, reviews, and my own usage (no scientific evidence to back any of it) it seems that seafoam and Amsoil fuel cleaners work well. It’s certainly not going to hurt anything to add a bottle of it in the fuel tank once every 3-5k miles that’s for sure.

 

Has Toyota or anyone attempted to find what commonality these failures have ? Like survey if owners to driving habits and conditions, fuel brands and grades, etc. there’s so many with 200k plus miles without issues. A local just hit 160 on his 18 trd or and frequently tows loads I wouldnt want behind my 1/2 ton

 

That would be prudent on their part , but I’m guessing they are not . Just paying the warranty claims as they come in , the part that really confuses me is this same engine is being used by Lexus in a few models without any real problems , a friend of mine is a master Lexus tech and he said he has not seen one Lexus Gr-fks come thru the shop with a valve issue

 

I kinda meant in the actual published maintenance schedule, not a sales pitch.

Also "alongside the regular oil change" would be every 10k miles, not 5k like his service advisor suggested.

 

He may have only said 'regular oil change' and I added the '5,000' miles thinking of my previous vehicle.

I suspect it's not in a published schedule and have not been able to find anything at this point. Mine didn't come with a manual so I need to download one anyway. Probably a good idea to get a later one as well.

 

I have some more information, mostly in the form of pictures of my injectors and the intake manifold. I also learned they pull the motor to change the head and after watching a decent YouTube video on a complete teardown, I do understand.

I've also learned that these engines have both direct and port injectors as do Lexus models with this motor and unlike the Highlander and other Toyotas with the 3.5l motor. That may explain why the #1 burnt valve syndrome is more of a Tacoma problem that other Toyota models but still doesn't explain why it's happening. But now that I know the issue is with the direct injector, it changes my understanding of how the injector gets dirty in the first place - it's combustion byproducts that foul it, not contaminated or dirty fuel. That's not to say that some fuels may burn cleaner than others but that's a different topic. But this new-to-me knowledge now makes me wonder just how well any fuel system additive can do much to clean an injector contaminated with combustion byproducts?

Anyway, on to the pictures. The service manager explained that the tech had brushed off some of the buildup on the injectors but much of it could still be seen. And as he explained, they're all dirty so I don't understand why it's always cylinder #1 that fails with a burnt valve? And why are the intake manifold passages dirty? Is the overlap between the closing of the exhaust valve and opening of the intake that large?

What I find quite discouraging is the service managers answer to my question "can I expect this problem to occur again in another 40-50,000 miles". He said yes, most likely. And no it won't be covered a second time. As I've mentioned before, this is my 7th Toyota and I've never experienced a major failure and most were driven well over 100,000 miles so I hate the thought that I shouldn't keep it indefinitely.

 

Thanks for the follow up post. It sucks to here about this issue on our beloved Tacos but discussing and learning about the problem more will hopefully yield beneficial results at some point. I think it’s a pretty far stretch of the tech to say “most likely” to this happening again in another 40-50k miles. We’re gonna be at almost 1.8 Million 3rd gens produced next year and you can hardly find any info on this problem online outside of these forums where some have posted about the issue. I’m not saying it doesn’t happen, maybe more than we realize but it certainly is not the norm, the majority or to be expected in the 100k+ lifespan of the truck. I asked my dealer about this issue who services a lot of Tacoma’s and they looked at me like I was from Mars. Said they see very little problems on these trucks and usually just do minor work and maintenance.

 

The service manager handling my case has been with Toyota for 26 years and has seen over 20 of these cases with the 3rd Gen Tacos so I'm inclined to believe he has some insight into it. But as you say, it doesn't explain the millions that will never experience this. But it's not a stretch for me to believe that with the problem being unique to certain trucks and as such it's likely those few will experience it again. It's inexcusable that Toyota doesn't have any response or answers on this issue.

 

More useful info - Toyota has an injector cleaning process where they disconnect the fuel rail and pressure inject a cleaning solution through the injectors. The tech that worked on my engine recommended this be done every 30,000 miles or sooner. He also said he's never performed a second head change for this problem. That's not to say it doesn't happen a second time, some might choose to have the work done elsewhere to save money over what Toyota charges since it's no longer a covered service. Or it may not happen because once bitten, twice shy and people regularly used fuel injector cleaners or have the process performed.

 

Thanks for coming back with the follow up. I'd love to see the data on the limited numbers of these out there, there has to be some common denominator, location, elevation, driving style....something.

 

Yeah, I'd love to see some of that data as well. And something to point to any common denominator.

 

There's a sticky about the 3rd Gen engine issues. Unfortunately, it is mostly a bunch of links without much in the way of conclusions:

https://www.tacomaworld.com/threads/2gr-fks-engine-problem-failure.774579/​

 

Thanks, reading through them now.

 

You're welcome.

 

Not True. I have replaced the heads on 2 Highlanders for this issue.

 

Did the dealer diagnos the route cause of the burnt valve? Burnt valve is usually a seating issues (bad valve seat) or manufacturing defect. The bad seat causes the heat exchange from valve to the head. Perhaps a poor cooling in that area.
Did they get final fuel trims? If there was a lean condition on that bank due to injector(s),
Long trim on th bank would be out of norm.

 

This! If this was a lean fuel issue, there should be a host of codes stored, and fuels trims should be at the edge of their limits. I find it very difficult to believe that this is anything other than a manufacturing defect relating to a valve system component.

 

Are they running positive crank case pressure into the intake? ie burning oil vapor? This was a common problem on DI VW and Audi engines. So much so they had a process to blast valves with walnut and went through a few different iterations of breather valves on their intakes. Perhaps long term coking on some valves combined with lower than mid grade fuel will cause a perfect storm of issues. Referencing my time as a VW, Audi and Toyota technician I never saw this issue when I was at Toyota on Tacoma's however I was a used car recon tech and did not handle alot of warranty work.

 

I can guarantee Toyota has their eye on this. They want to know why engines are failing under 75k or less.

None of us know the data on how many of these failures are happening except for Toyota. So, we can't assume this isn't a big issue. It could be more common or less common than everyone is speculating.
At 4k at a clip to repair plus the cost of a rental car, even if it's a low amount, Toyota is looking into it. I can almost promise that's a fact.

If Toyota can pinpoint what is failing, they may have financial recourse against who manufactured the defective part.

 

Seems legit...this engine uses an atkinson cycle...it just runs too lean.

to everyone asking about oil catch cans or additional fuel filters...you don't understand what's happening...none of that would do anything. the engine is running too lean, fuel filters would make it worse, oil catch cans would literally do nothing...etc etc. Disabling the atkinson cycle is the only thing that would help. I believe the tunes offered by a few companies on this forum do just that...I'll be installing mine asap...now that I got my dongle and laptop up and running that is. My '17 thankfully hasn't had this issue nor the fuel pump issue...with 126k I'm sure to be fine but...I'm still installing the tune (it'll shift better and up the power anyway) but it'll also disable the atkinson cycle...I think...don't quote me.