Oil Analysis, Redline D6 ATF 30k miles

I know you didn't ask me but while my typing fingers are limber...

Your Pentosin has a slightly lower viscosity @ 100c than the D6, 5.6 compared to 6.3 according to both companies' PDS sheets. This makes them both (and all LV ATFs) pretty darn thin. I'd say most likely a wash with regard to mpg, although if there were a way to measure the mpg very tightly, the Pentosin would have a fractional edge.

It's an excellent WS substitute, imo (flame suit zipped up, duck and cover), as you well know.

 

Yeah, lets get back on topic!

 

Interesting. I will not run my engine on pure Oxygen.

This still does not answer the question of what symptoms an owner experiences as the EGR system gets choked down.
Why would someone think the head gasket is at risk? The VVT system still controls effective compression ratios, correct?

So as it gets choked down the 21% EGR becomes less because the valve position might feedback to the ECU but there is no way of knowing the actual flow rate, correct?
So what happens then? The fuel/air ratio should remain be clean, correct?

 

See post #69 and click on the link posted, "EGR & Intake Manifold Clean Results | PriusChat"

 

Did that. Watched the videos for the EGR Valve and Cooler and intake manifold cleaning. I'm on board for the cleaning and OCC install. Frankly some of the pictures do not look that bad.

I didn't go through the whole 10 pages of that thread looking for the answer to this simple question:
What are the symptoms of having the EGR system slowly getting choked down with carbon build up?
How bad is it to simply wait for the CEL and code? Or wait for the elusive symptoms????

 

Ultimately, the "symptom" it's working to prevent is a blown head-gasket.

For context, change a couple words:
"What are the symptoms of having the oil slowly getting dirty with contaminants? How bad is it to simply wait for a CEL and code?"
Preventative maintenance > fixing problems.

Other symptoms you may see before the CEL:
-10% dropped MPG
-Rough engine start
-Rough engine performance when acceleration exceeds the power bar.

 

Maybe the head gasket is just the wink link in all really high mileage Gen3's?
Will I definitely get the other listed symptoms if I wait for the CEL/code to show?
I think my car got the updated intake manifold, which was Toyota's fix for the 'knock at cold start' issue, correct?

Just for grins, I contacted a prius specialty shop listed in one of the many many threads on this subject to get a quote on having a shop perform the '3 item Clean Up' and OCC install.
The reply was interesting!!
He said I could post it here. But I said I'd send the trimmed response to him first before posting, and I wanted to find the thread where I found his shop listed.

 

I currently have redline 0w-20 in the transfer case and know that ZDDP will also thicken the oil viscocity-wise. Someone recommended to also try redline engine oil earlier on thread so just wanted to post the negatives of redline oil and what "experts" here had say about running that brand on here & rile people up heh.

 

Still Off Topic... Where should this be posted?

I can see the 'cold start knocking' being bad for the head gasket, but why would decreased EGR performance harm a head gasket?
The O2 sensor and knock detector keeps detonation at bay while up and running.
'Cold Start Knocking' is most likely puddles of oil/water emulsion in the bottom of the intake.

So, I asked a shop that I found in a related thread for a quote on having this service done. I got permission to post the reply below:

Bill,

Long story short, we don’t recommend proactively cleaning or replacing the EGR cooler, EGR valve or intake nor updating the ECM software unless it is symptomatic of a failure of these system.

You’ll have a pretty obvious CEL code for the EGR and/or a cold soak rattle. It isn’t worth your time or money on the small chance you have issue crop up, as the repair for the issue is the same as preventing it (which is unlikely to happen overall).

The majority of the vehicles that experience the concern are burning oil at high mileage. With routine 5,000 mile oil changes (not 10,000) using a Dexos rated 0w20 synthetic oil you’re less likely to have the concern. The occasional spirited acceleration seems to help prevent moisture and oil vapor pooling in the intake. For that I only have anecdotal evidence, but it seems to help.

Replacing the intake, EGR valve, cleaning the EGR cooler runs around $1300 plus tax using all Toyota Genuine parts, with the most updated parts as available, including spark plug replacement to the updated plugs. There is a considerable amount of labor to get everything apart.

We do not install oil catch cans - OEM repairs only. Sorry on that one.

I’d encourage a DIYer to make the preventative repairs themselves as they are saving a ton of time in repair labor, but I have a hard time selling a guest $1300 in work that is designed to prevent an issue they might not have. Doubly so when preventing it costs the same as fixing it.
Cheers,
John
Owner, carspecmn.com

I think he may be onto something with the "spirited occasional driving".
Could it be the worst EGR clogging is on cars owned by drivers that NEVER use full throttle and stay mainly in the <1/2" of throttle pedal movement?
You know what I mean? The drivers that monitor that silly display to save a-half-a-buck a week and give all Prius drivers a bad name by driving SLOW?

I thought about posting this in other EGR Cleaning threads but there are so many. Should I post this elsewhere?

 

I would post it in the newest post on that subject or start your own brand new one.

 

@Bill Norton, what are you driving? Do you still have a third gen Prius?

 

I wouldn't post it anywhere because the first part of the information is false, we're already cleaning the components with threads everywhere on it with a helpful video tutorialprovided by nutzaboutbotz. And the information is redundant, there's no need to create another thread to cause anymore "confusion" because some refuse to read existing threads that thoroughly covered the topic already.

 

Yeah don't be surprised if you get pushback, telling owners who've already waded through, cleaned their clogged EGR system, that there's no problem.

If you have a 3rd gen (your avatar doesn't say), do yourself a favour and check the condition of the pipe, to get some idea of the overall condition. Video by @NutzAboutBolts on the subject, pinned at the top.

 

Just bought a '11 Prius Five w/ATP, 181k miles. Great service history. Great fuel and oil economy!
Love the crude Autopilot functions! Haven't tried the Self Parking yet. But it's my fuel hog.

Yes, thoroughly covered. But the results of all this clean up labor have not.
What do you experience when you have a squeaky clean EGR system?
What do you experience as the miles build to the next 100k miles?
>Increased MPG or any measurable performance improvements?
>Less oil consumption?
>Never a 'Cold Start Knock' again? (which I heard once with my previous Gen3. I'm starting to think it's a separate issue.)
>Less likelihood of a head gasket failure? How is that even proven?

I'll look someday. And It may be as bad as others' after 10's of thousands of miles after all the clean up work.

I guess if it got bad enough where you got the CEL, there may be a measurable difference after all the cleaning. EGR's get dirty in use. Period.

I'm positing that if you use full throttle for a while, once in while, it may not build up in the EGR circuit as bad as some of the reports here.
Are any of the very clogged ones coming from a car that has recently seen FULL Throttle for ~1-3 mins on a steep uphill?
Or are the clogged ones mainly coming from the fuel economy 'pinchers', that never see Full Throttle?

 

Check the pipe and you'll know.

 

Now there is a reminder to check the title of the post before commenting! What was we chatting about?

 

Is this referenced in any service manual?

And what exactly are these "consequences"?

Do you know what could have been if you never performed all this 'Clean Up' work?

But Techron cleans the injectors, intake ports and combustion chambers. Downstream from combustion all the detergent properties are burnt, no?
____________________________________________

I just bought my second Gen3 and started down the EGR Rabbit Hole!
So I contacted a Prius specialty shop for a quote to have this work performed.
He advised against it. He turned down work !!!
I posted this in another thread that went down the EGR rabbit hole and was told I should post this here:
___________________________________________________________________________________

I can see the 'cold start knocking' being bad for the head gasket, but why would decreased EGR performance harm a head gasket?
The O2 sensor and knock detector keeps detonation at bay while up and running.
'Cold Start Knocking' is most likely puddles of oil/water emulsion in the bottom of the intake.

So, I asked a shop that I found in a related thread for a quote on having this service done. I got permission to post the reply below:

Bill,

Long story short, we don’t recommend proactively cleaning or replacing the EGR cooler, EGR valve or intake nor updating the ECM software unless it is symptomatic of a failure of these system.

You’ll have a pretty obvious CEL code for the EGR and/or a cold soak rattle. It isn’t worth your time or money on the small chance you have issue crop up, as the repair for the issue is the same as preventing it (which is unlikely to happen overall).

The majority of the vehicles that experience the concern are burning oil at high mileage. With routine 5,000 mile oil changes (not 10,000) using a Dexos rated 0w20 synthetic oil you’re less likely to have the concern. The occasional spirited acceleration seems to help prevent moisture and oil vapor pooling in the intake. For that I only have anecdotal evidence, but it seems to help.

Replacing the intake, EGR valve, cleaning the EGR cooler runs around $1300 plus tax using all Toyota Genuine parts, with the most updated parts as available, including spark plug replacement to the updated plugs. There is a considerable amount of labor to get everything apart.

We do not install oil catch cans - OEM repairs only. Sorry on that one.

I’d encourage a DIYer to make the preventative repairs themselves as they are saving a ton of time in repair labor, but I have a hard time selling a guest $1300 in work that is designed to prevent an issue they might not have. Doubly so when preventing it costs the same as fixing it.
Cheers,
John
Owner, carspecmn.com

I think he may be onto something with the "spirited occasional driving".
Could it be the worst EGR clogging is on cars owned by drivers that NEVER use full throttle and stay mainly in the <1/2" of throttle pedal movement?
You know what I mean? The drivers that monitor that silly display to save a-half-a-buck-a-week and give all Prius drivers a bad name by driving SLOW?

In summary:
Are there any high mileage Gen3 owners that have never gone down the EGR rabbit hole,,,,
And are doing fine?

EDIT:
Just asking questions and looking for answers.

 

I just recently hit the unignore button, on everybody. I think I'm gonna employ it again.

 

You want to give him a clue but know it will go in one ear and pass out the other...

Maybe he can get an answer in the ABS pump thread...

Pixel XL ?

 

The point of EGR is to partially fill the combustion chamber with inert gas that will not affect the next combustion cycle. If the circuit clogs, that space is going to be occupied by oxygen- and nitrogen-bearing air. That's going to allow different (leaner) combustion characteristics than were originally planned, and usually involving more energy in less time- detonation. This can increase blow-by and put additional pressure on head gaskets.

I haven't owned one of these long enough to see the impact firsthand, but I've dealt with EGR causing similar problems in other cars.