Professional EGR Cleaning Resources

Noticed in the owners manual for a 2014 that Toyota recommends high quality gasoline with extra cleaning ingredients. Thought this sort of odd and maybe it's a recognition of the problem with clogged intake manifolds. This would be Tier 1 grade gas. All name brand gasolines EXCEPT Amoco, Gulf, and BP. Can't go wrong with Mobil.

 

Your doing great...... but expect the Head Gasket problem no matter what you do...
Get a new water pump at no later than 150,000 easy change out....
Also expect Inverter Failure and Brake Pump and Accumulator failure. Brake pump will start running alot.... when failure begins.
Inveter goes out without warning.
I know about all of this because it all happend to my 2013 and when inverter failed was 1100 miles from home.

 

The only thing gas can help with is clogged fuel injectors which is not an issue on these engines. Maybe the back of the intake valves in the head but not if the engine burns oil.

 

This is a good test to visually confirm where all that coolant has been going.

But if you see a 'drip - drip', using a borescope, from the head gasket with 4 - 15 PSI coolant pressure,
that drip - drip is happening at every hot shutdown of the car. The coolant stays pressurized for a while after the engine is off.
And then the rattle, stumble on the next start up.....

Oh well, you ran out the clock on the chronic Gen 3 head gasket problem. Time to open that dusty old billfold.

Some hope that you can delay this by keeping the EGR system clean, by doing a big cleaning every 50k mi or so.

Another hope is: just disable the EGR so there is no chance of UNEVEN EGR FLOW. ( the suspected culprit )
Also get the latest SW update that has something to do with the water pump speed at high power.
The European TSB even mentions that the SW update may have benefits in regards to Head Gasket life.

I've done both of the latter and I honestly can't see a difference in MPG. And I have more HOPE now.

 

Of course the coolant system is a sealed system with the cap providing a ~15 psi relief.
That relief is the over flow port you are talking about.
That port comes above the pressure seal. If you open the cap with pressure on it, while the engine is hot, the steam will exit that port and not get you.

Do this test.
Arrive home with a fully warmed up engine.
Go inside. Kiss the wife. Take a pit stop. Walk back out to the car and open the coolant reservoir. You should hear the pressure release.

When the engine is running the combustion pressure enters the coolant through the failing head gasket.
There's a test for reading what's in the coolant in regards to head gasket failures.

 

"Hotter"? As in combustion temps? 'Uniformly'? For the exact same HP output?
As in cruising down the level road at 60mph the engine may be making ~21 hp. With or without EGR, true?
How much hotter would the combustion temps be in this scenario? Who knows? You and I don't.....
What happens at Full Throttle? Is EGR used when that is asked for?

I know my ECM is reporting 'EGR Control Circuit ...'. My check engine light is on.
I'm hoping the ECM adjusts things accordingly because of not having EGR flow (or uneven flow) at certain times and power usages.
And as always, there is a Knock Sensor in the system to keep things out of the detonation zones.
I can't detect any noticeable change in MPG.

( I do feel a smoother throttle response.
Less hesitation/not really a stumble - but no immediate response to adding throttle. It feels more immediate now adding throttle.
I think I might be able to tell in a blind test with and without the ERG connected.
That would eliminate any Placebo on my part, correct? I just need a helper to fiddle under the hood and not tell me if it's connected or not.)

Only time and miles will tell if cleaning the EGR routinely gives you another 100k miles before the head gasket fails.
And the same for Deleting the EGR system.

I'm not on my own with this theory. O'l what'shisface inspired me to Pull the Plug on the EGR system. And there are others.
Only time will tell...

 

Yes the intake manifold has those small ports for the EGR to flow through. They clog unevenly due to longer path for the hot EGR gasses, so the farthest gets the coldest and the most carbony crud to condense out in those tine ports.
Yes, a new PCV valve is cheap insurance while you have the intake manifold off.

Those other items are good practice buy not related to the chronic head gasket failures.

 

I would guess the lack of flow through the EGR and through the porch and to the engine raises the internal combustion temperature a bit I guess that may be helps the head gasket fail creates a hotspot something this could happen in any engine.

 

great idea... i plugged both ends and pourd bottle techron in it... came out excellent....

 

My 2011 Prius has periodically had a shaking/rattling upon the gas engine kicking on. Just now at 204,000 miles it done it BAD and threw the engine light on. The car still runs like a champ once it stops but now I have parked it until I get it checked out. My first search mentioned EGR problem. Do you know if it is expensive to have it fixed? I also read that there may have been a recall issued on the 2011 model? Do you happen to know if there has been? Thanks for reading!

 

How is the coolant level? Has it gone down? If it has gone down, it’s likely a head gasket...
When did you replace the spark plugs? Have you ever cleaned the egr system? Cooler, intake manifold,
etc.?
Depending how mechanically inclined you are, you could replace the head gasket yourself.
You can also change the plugs, and clean the egr circuit yourself.

If you can’t do the work yourself, then you’ll have to pay someone to do it. And of course, that
will cost money.

 

The egr is closed at full throttle and during low speed engine operation.

A dealer will charge about $1000 to "upgrade" the egr system with a new stainless egr cooler and a new egr valve. He will also change the ecu software.

It won't help a BAD startup rattle that goes away and runs smooth after.

Updated parts for your 2011 include revised pistons and rings, revised intake manifold, revised egr valve, revised head gasket and other hybrid related parts like the inverter. The engine parts are best implemented in a professionally rebuilt engine, typically not your old block, crank or connecting rods.

The real question is what is wrong with your engine? A borescope inspection can be definitive; older methods like a coolant test for combustion gasses, leakdown test or compression tests often produce false negatives.

Car Care Nut HG Borescope at 660s

Shudder video

Is there any short term tricks to make the engine rattle less as I determine my options? Some loosen up the engine coolant reservoir cap to avoid coolant seeping into the cylinder overnight. They carefully watch the coolant level to avoid major overheating.

PS
Scotty, it's best to start your own thread instead of jumping on another

 

My 2011 has 209k on it and for the first time in it's life it has tripped the check engine light. It has started shaking and rattling upon a cold start. Seems the most talked about cause is carbon in the EGR valve, cooler and pipe, but got no EGR code p0401. And NO coolant is missing! - Instead I have 4 codes. 0300, 0302, 0304, and another 0302 with two arrows(up&down). I am no machanic by far! I just try to be a DIY'er on a tight budget trying to avoid the Toyota dealership price, so I don't even know what that last code means?
Anyway, my question is where do I start? I figure the spark plugs? Then the coil packs? Then injectors? Then EGR parts? What about the intake manifold? What about the throttle body? But like I said, I really have no clue. Just playing mechanic... All I have ever done to it is change the oil regularly, tranny fluid, coolant in radiator and hybrid system, and brake fluid. - Any and all tips/suggestions will be greatly appreciated! - Thx 4 reading!

 

You already posted earlier in this same thread.

Doing any of these is a waste of money when you know the engine runs fine after the startup rattle. The plugs, coils or injectors won't act like that and the same goes for the egr and intake.

The codes you have are misfires caused by coolant fouling.

Get a borescope test.