Oil Analysis, Redline D6 ATF 30k miles

I was replying to Grid that engine oil with ZDDP damages the converter. Redline oil touts a ZDDP package that really helps with the valve train noise on my G2.

But this thread is ridiculous.

 

See what happens when you delve outside of the Gen2 threads.

 

I doubt there's any 3rd gen without EGR clogging. More likely just different degrees of owner complacency, and it is something that is a lot easier to deal with earlier than later.

 

Its exhausting.

 

OFF Topic:
What are the symptoms?
How bad before you need the cure?
What's the best thread on this subject?

Thanks, I'm new to this subject....

 

Typical symptoms I have experienced are a reduction in mpg when on a defined route. I have seen as much as 4 mpg reduction when traveling to and from work (38 miles one way) that I have been doing for almost 5 years now. You’ll also see the ice requiring more use on hill climbs (I have one significant one on my work route and when I have to constantly put the pedal to force it into the PWR range I knew something was up).

I’ve done the egr circuit cleanse twice to our 2010 and have done the job 6 times overall. The cooler at 120 k miles was caked and I consume a quart of oil every 5 k miles. At 173 k miles, the cooler was just as bad, so I’ve determined for our situation that every 50 k miles seems about right for the egr circuit cleanse.

Hope that helps.

 

There's several threads but this one is the most trodden I think:

EGR & Intake Manifold Clean Results | PriusChat

As to symptoms: it's probably best to get ahead of them, pretty much all 3rd gen EGR's clog. A relatively easy check is to remove the connector pipe between EGR valve and intake manifold, see what it's inside looks like. If it's moderately carbonned up, then the EGR cooler is likely due for cleaning.

I cleaned ours very early, and I get the sense it's progressively harder to clean, in particular the cooler, the more clogged it is. Maybe for sure clean it by 100K miles?

The car will display warning lights and code P0401, but this is usually when the EGR system is REALLY clogged.

@NutzAboutBolts has done video's on the pipe check and a full EGR clean, pinned in the 3rd gen maintenance forum.

 

Just looked at the video. Lot's of work but no parts required! Maybe a cup of collant.

Only,, I don't see any info about 'Symptoms'.
I'm at 182k miles with this '11 Gen3 I just bought and it runs great and seems to be getting very good fuel and oil mileage.
How bad is it to wait for the light and code?

(I didn't get into the thread you linked, but thanks for the help !)

 

Yeah have a read through the thread. When I did ours, at the outset I drained 2 liters of coolant, at the radiator drain spigot, into a clean container. That dropped the level of coolant to be below the EGR system, so no need to clamp hoses, and zero spills. You just need to be careful: lift the cooler out without tipping, there's a wee bit of coolant trapped in the back corner. You can pour it in with the rest that you've drained.

When you're done, all the hoses reconnected, pour coolant back into the reservoir. Maybe burp the main hoses a bit has you go. You can also leave the coolant vent screw open (2010, 2011 model years), or leave the topmost hose loose (2012 on), until coolant reaches that level. The reservoir level will likely end up slightly high, but will settle with a day or two driving.

Clamping the hoses is a bit absurd anyway: you clamp the hoses that run into the cooler, disconnect them, and the all the coolant in the cooler promptly drains out.

I'd highly recommend to do the intake manifold cleaning too. It tends to act as unofficial Oil Catch Can for the PCV circuit, and also is the final leg of the EGR gas circuit.

And while the intake manifold is off is an easy time for OCC install...

Oil Catch Can, Eliminate that knock! | PriusChat

Take the aforementioned EGR pipe off (there's a @NutzAboutBolts video on just that removal), see how it looks. That's an easy exercise, about an hour. The main symptom? you have a gen 3 with 182K miles, lol.

 

Thats how we do it here.

 

Thanks again for all these helpful pointers!

I understand the usefulness of an Oil Catch Can. I had a 2 VW TDI's before getting my first Gen3.
So I understand intake manifold/EGR valve cleaning... Yuk with the TDI's. You never saw clogging like those get.

How about a self-supported FIRE cleaning of an intake manifold?!! Just the first 2 minutes shows how it's done!

But, again,,, What are the symptoms? What do you experience before you eventually get the light and code?

(I drive a BEV. 58k miles so far. I should open the hood someday and add washer fluid. But I don't like working on cars even that much anymore....)

I am capable of doing all this work on the fabulous Gen3 I just bought. But I'm not going to do it without cause.

It had a great service record. But, maybe the previous owner had this work done by an independent shop and it's not on Toyota's service history. Know what I mean? I don't want to get into it and find it didn't need the work.

 

How many miles on your Prius?

Are all of these records from a dealer?

Did you meet the previous owner?

Were they the DIY type?

If above 100k miles and only dealer service records, it’s safe to assume that the egr circuit has not been addressed. The previous owner probably also believed in the “closed hood” philosophy for maintenance. Cause the dealer maintains it, they would let me know when something is wrong.

As @Mendel Leisk said, you can pull the egr pipe and see a glimpse of the situation.

Good luck .

 

Sometimes repeated cold start knock, real cold start knock where it seems like the engine is trying to jump out of the engine bay.

Sometimes a slight shudder during light, gas engine involved acceleration, from mid-teens mph thru mid-20s or so. Feels like the road has a high-frequency washboard pattern to it.

Sometimes reduced mpg as Ray reports.

Sometimes P0401, but I personally feel this one is overplayed and only happens in some cases. Complete blockage within the intake manifold and complete blockage of the cooler can and do occur without the valve and it's sensor ever knowing there is an issue. No cel, no code. This may even be the case in the majority, in my opinion. Also, the popular Priuschat test of "checking the EGR pipe for blockage" is a marginal test, again in my opinion. The pipe, and the EGR valve rarely (if ever?) show complete blockage. It's the intake manifold and/or the cooler which block completely. You may march to your blown head gasket with no symptoms whatsoever. It will be popular opinion around here that at 180k+ miles, you're well on your way, and somewhat lucky you're not already there.

Okey doke.

That's a definite maybe. Only a handful of Priuschatters have an awareness of this being an issue. Well, maybe dealer techs (they likely aren't talking too much about it, in my opinion) and higher level, honest Toy indy's, such as Carspec:

EGR circuit concerns from a Toy indy shop | PriusChat

 

So you're saying a blown head gasket will be the result of not having the normal amount of exhaust gases mixed in with the intake flow?
How would that be explained?

Some say the head gasket is just the weak link on really high mile Gen3's.

I once heard the 'cold start knocking' on my previous '10 Gen3. I chalked that up to driving slowly around town on a rainy day and never getting the engine thoroughly warmed up. At the time I read about an updated intake manifold design to prevent that. And I didn't know about EGR clogging as an issue. That Gen3 had less miles than this one.

(That car gave me a taste of limited EV driving. Sold it and for a Volt, which gave me a taste of Real EV driving.
Sold it for a Chevy BEV,, the 82 mile one. This '11 Gen3 is for the GF and to have a good road trip car.)

 

The allam power cycle is an extreme example. It's a new type of engine used by power companies that uses fuel, pure oxygen (3%), and 97% EGR. Because of the immense use of EGR this engine achieves 59% thermodynamic efficiency, generates no NOX, and eliminates catalytic converters . If we were to run an engine on pure oxygen without any EGR the engine would explode into puddles of liquid metal.

In comparison, the Gen 3 Prius engine was designed to run on 21% EGR and has a thermodynamic efficiency of 38%.

 

I run Pentosin ATS-1 LV does that mean I will have even better fuel economy? My old Prius (now my sons car) has 300K on it and never had WS put in

 

Yes sir.

Way high cylinder temps from lack of, or zero flow of exhaust gas to combustion.

Yes, they do, and they may be correct. But they may be incorrect. So personally, I feel looking after the EGR circuit makes the most sense. If they're right, I've wasted my time tending to it and will be doing a head gasket job regardless. But if they're wrong... I don't imagine Toyota will ever be telling us why the turd gen Prius blows head gaskets, but who knows?..

Your story is indeed one of the likely ways to induce an isolated cold start knock. An extreme overnight temperature swing with a big change in barometric pressure is another. Firing a cold gas engine up and shutting it immediately down (cold soak) is another. The updated IM may or may not help the isolated cold start knock issue. My opinion from reports I've read here is that it's inconclusive at best, with a lean toward it really doesn't help at all. Isolated cold start knock is a turd gen fact of life and a non-issue, imo.

 

You know we all seem to be getting along just fine right now. Maybe we need Fred's House of Alternate Transaxle Fluids?