NEW!!! Service Bulletin for Engine Knocking at Startup T-SB 0012-10

@Mendel Leisk thanks! Currently at 145k miles. I only bought it a year ago at 129k miles though.

Yeah, I was planning on doing the whole cleaning + OCC install, but I was going to wait a bit. I was wondering if I should take it to the dealership first though, due to the knocking. I don't know if I've already damaged something, but if I have, would the dealership cover it in light of it having been noted back in February?

 

Yeah doesn't hurt to check with the dealership. I wouldn't have high expectations, but you never know. If Toyota will acknowledge it under the Warranty Extension Program, that was issued for the EGR. With Toyota Canada we got a notice in May of 2017 (SOSH-W11-1A). If you google image search that number you'll find my previous image post. I'm sure there's similar in the States.

The only thing: it seems like almost without exception the only way this gets resolved completely is by DIY. In other words, Toyota's paying lip-service to the issue, but doing nothing substantial.

 

With your car sitting for a while and being cool/colder weather this is more likely to happen. I wouldn't worry about it, this cold start knock happened to me after a week away during Thanksgiving and started up on a cold/wet day (48F in Bay Area is cold to us), even with oil catch can installed. I put tranny into Drive so my car didn't knock too long, just a couple seconds.

If it has startup knocks often then it's a different story.

But be sure to perform EGR system cleaning & install OCC as Mendel said and gave detailed info, before any damages done.

 

I had the OCC off yesterday, what nasty gloop was in there. Kinda takes the wind out of the clean combustion sail.

 

I just spoke to a service manager at the dealership, and he said he does see that they did an EGR valve replacement and an EGR cooler gasket back in February, and whatever they did is still under warranty. He said to bring it in and they can take a look at it tomorrow. If it's the issue under warranty, the diagnostic fee is waived. Otherwise, it's $150.

I'd rather not pay the $150 diagnostic fee, but it certainly sounds to me like a similar issue to the above mentioned warranty repair they did in February. What do you guys think?

 

I have not carefully read your current issue, but based on what you report here, I recommend you print out a parts diagram of the whole EGR system, with part names, numbers, and prices. Then when you're talking with them, you can see what exactly they're talking about.

In general, dealers, and mechanics in general, love to replace parts, billing for the labor and getting some markup on the parts cost. They really don't do cleaning. For the EGR system, cleaning the EGR tube ("pipe"?) and the EGR cooler are what are generally reported to be what is needed. So if they replaced the EGR valve and cooler gasket, they did other stuff.

Don't be surprised if the sales guy you talk to has no idea what you're showing them. Maybe they'll learn something.

 

Sounds like they replaced the yellow-highlighted portion. All of the cyan hatched is also prone to clogging. Really, NONE of it must be replaced; all of it is eminently cleanable. Dealerships are not willing or capable of doing this, due to the time involved, rules and reg's, whatever:


Sadly, I don't think I've heard of a SINGLE owner who tried to resolve EGR clogging issues through a dealership, successfully. It's a hopeless endeavor, and the only solution is to roll up your sleeves, or get in touch with nearby DIY'rs who can help.

More info in the attachment:

 

I dropped off the car at the dealership earlier today. They said they'll check it out in the morning. I had them note the engine knocking noises on startup in the morning, and engine rattle during acceleration upon low hybrid battery and ICE on.

Really I'm just hoping the dealership will check for any damage and fix accordingly under warranty, considering I brought the issue up with them back in February, at which time they did attempt some type of "fix" (which evidently has not held up, and as we know here, would not have held up without a proper cleaning) under warranty. After that, I'm planning on doing the cleaning and installing an oil catch can myself.

 

How can I tell it's a problem from that EGR bulletin versus ((SOSH-W11-1A) needing new spark plugs?

Yes, idles rough at times.
Yes, had made that little knocking noise a couple times.
Yes, I got a new AGM battery and my average mpg only went up to 36 briefly when I drove about 40 minutes one way. It's now time for more gasoline with an ending average mpg of 33.9 mpg. My car is barely loaded up with weight. I could deal with a bit mpg in the high 30's from short trips, but not even mid-30's is awful.
No, I haven't notice a sharp decline in acceleration.

Yes, I am still under warranty, but spark plugs are not covered and are costly.

Mileage is about 96,000.

Yes, I tried blaming not as good normally mpg on short trips at first. Then I blamed I tried blaming it on needing a new AGM pretty badly due to it going down to low 30's on average.


No codes at all!

Thanks in Advance.

 

It wouldn't hurt to clean the full EGR system at 96K. Start with the pipe; see what it looks like.

Clean the throttle body if it hasn't been done in a while.

Trying a fuel injector cleaner might help too.

Also, feel the wheels after an extended drive: if any feel markedly hot it's likely dragging brakes.

 

Interesting video:

 

Interesting, yes, that the presenter never offers an explanation for why disconnecting the EGR valve (thereby suppressing EGR) would be diagnostic of a problem resulting from clogged EGR passages (thereby suppressing EGR).

Fighting back the urge for the "Er... what?" emoji....

 

Must be great to be you eh?

 

Drip that nasty carbon all over those bricks!
Soak the whole thing in GASOLINE overnight!

Make sure you watch the news for and explosion and fire!

I have NO COMMENT on this matter!

 

I left a comment on the YouTube loc, basically "thanks for the info but stop drippin' in the planter fur chrisakes!"

 

So is it possible to have the knock at startup but a perfectly fine head gasket?

 

I think so. I suspect what causes the knock is "fluid" iin the cylinders. There's been lot of reports of cold-start knock, if you previously started the car, just ran it a few seconds, then shut down. I've had that myself. Once...

Someone here (maybe @Cosmo Tigato ??) posted a pic looking down an intake port, and you can see a little ponding "something", atop the valves. Might have been water condensation?

But if start-up knock is a regular event, coolant level in the reservoir is dropping, check engine light is on, and you've got codes like P0300 and P0301, more'n likely head gasket.

 

Interesting. If the cold-start knock is the primary contributor to wear on the head gasket, I wonder if cars that see more highway miles (less on/off cycling) fair better in this regard? Or, if by extension, taxis used in urban environments are seeing blown headgaskets earlier in their lives?

I also suppose that you could have a car that had unrecorded head gasket repair sometimes in its life (outside of a dealer), but NOT an EGR cleaning, so you've got a relatively fresh head gasket, but a car that still starts up terribly and is headed for its second demise.

In my 214k 2010's case, the oil and coolant both look great but I'm hesitant to drive it more than necessary to determine coolant usage. I'd sooner get in there and clean the EGR system and inspect the cylinders before running it too much.

 

Condensation can build up over cold night in cylinders and cause startup knocks because Condensation/water cant be compressed.

 

"Condensation can build up over cold night in cylinders and cause startup knocks because Condensation/water cant be compressed."

Um...the cylinder would have to be FULL of water for this to be an issue....not just a bit of 'condensation'.