Is Head Gasket failure common in Gen 3?

Last time I spoke to this buddy, both those couriers were above 400k and 600k miles.
So they have been whistling down the road a long, long time. Way more time in a Prius than anyone on PC.

 

Yup, my 2010 HG went out this past summer with about 190k miles on it so had a new engine installed, and just before that replaced the battery packs, def put some money into her this year better last me another 200k miles.

 

The compression and expansion ratios of the corolla's 2zr-fe engine are both 10:1.

The advertised expansion ratio is 13:1 and the effective compression ratio is 9.5:1 on the 2zr-fxe of the Prius. Maybe with VVT the effective ratio can increase to 10:1 or a little higher - close to the Corolla? Possibly a little higher than 10:1 since EGR is anti-knock. I seriously doubt it would get close to a 13:1 effective compression ratio - the engine would need much higher octane to prevent knocking. It would still remain an "atkinson" engine since the compression ratio is lower than the expansion ratio.

 

Just check the pipe? Is that so hard, lol.

 

Why when blissful ignorance is so peaceful.

Or maybe the game show Press Your Luck returns and we cheer for “No Whammy”.

I’ll keep my every so often routine going and support those in my neck of the woods as time allows.

 

OK, I will!
And it will have crap in it! How much is the question, correct.

This is the easy to get to pipe from the EGR valve to the intake manifold, you are talking about, correct?
I assume the bigger issue is the EGR cooler, correct?

And I assume usage, driving trends and style, oil consumption and, some say, flavor of the gas used will all have a lot to do about how clogged the EGR cooler will appear.

Fair enough. I'll look at the easy pipe. And take good pictures.

But not anytime soon. It's winter. No heated garage. Worse than Canada weather....
And the car is mostly just sitting there. Me and the GF commute together this time of year in my BEV.
We leave that smelly gasser in hibernation! (I put an 'anti-sulfation' battery minder on it occasionally.)

Once again, it seems like it may be hearsay that: A choked down (or totally clogged) EGR system takes aim at the head gasket.
Where did this theory come from?
Someone theorized 'A lack of EGR flow, when it's expected, will cause Detonation'.
Well,, the engine has a system dedicated to avoiding Detonation, correct?

Good news!: I'm meeting the Bank Courier Bud for Celtic Music at a distillery this weekend!
We will talk about ultra-high mileage Prii ownership and maintenance!! And have a dram or two!

Bad news: We won't be taking the Smelly Gasser, even though it's on the other side of town. My town has a great DCFC network !

Good news:We'll be using 100% American-Made Energy.

 

If you've got some sort of garage, albeit unheated, if it's practical/secure, I would leave the charger on it constantly. For sure read the manual first, verify that's ok. Most smart chargers (well mine at least) are ok to do that.

 

did you clean the EGR cooler before the HG? how about after?

 

Mechanic cleaned it after.

 

A few questions for PC members who like to investigate and have time:
Is HG part # shared between prius and corolla engine of comparable years?
Is HG part # same for 3rd and 4th gen prius?
Was the HG part # revised within the 3rd gen?
THX!
I would love it to do it myself, but still have a daytime job.

 

And by doing this 'EGR Cleaning Routine' for yourself and your buds, hopefully none will ever experience a head gasket failure!
Is that the theory?

Hopefully engine coolant changes are also being done as recommended!
These two preventative maintenance items will assure never having a Gen 3 Head Gasket Failure, correct?

I'm just kicking it again,, How can any of this be proven, one way or another?

 

only by experimentation. Don't clean yours, you're a part of the experiment.

another way to prevent is to avoid overheating the ICE. shot down on the smallest indication of overheating.

 

OK, I'm in!
I just got back from a 1200 mi. high-speed Road Trip ! I'll post some dismal MPG display numbers,, there was a wind advisory.
Anyway ~ 4k / miles per qt. is my oil consumption, so the engine is not too bad:
Most of that was on the leg with the crazy headwinds pushing through at ~83 MPH GPS speed. The return leg was had very little oil consumed ! So actual oil consumption may be much less.
I suspect my EGR cooler is not clogged after that flogging!
Oil change due this weekend. ATF change too!

>> "Small Indication Overheating" ??? What's that look like?,, umm, how does one know there is overheating with a Prius?
Sure if a light comes on it's time to stop now,, not sure what that light looks like or what msg would appear.

 

Not sure how you connect the dots on that, but carry on.

 

An Italian tune-up?

 

Won't do much for EGR deposits I think. Maybe for valves, combustion chamber, but the EGR is a little back water.

We loaned swapped cars with our son and daughter-in-law recently, for about a week, while they were having car troubles. Anyway, it was mostly driven by daughter-in-law, who's familial background is Italian, and when we got the car back the mpg was down a bit, but the next tank it did pretty good.

 

EGR was at max flow rate, max EGT temps, Fuel Flow way up there, for hours on end.

The Italian Road Trip !

Eat a looks somethin like thees !
1st leg ---- TRIP A --- 264.1 Mi ---- 31.0 MPG ---- AVG 75 MPH
Later --- TRIP A --- 534.5 Mi ---- 33.1 MPG ---- AVG 71 MPH.
But Adaptive CC (love that ATP!) was set for 83 mph on GPS, 85 mph indicated. (I can post pics)

Just my Wild Azz Theory,,, just like the WAT of: Dirty EGR circuit = blown head gasket.

Who knows for sure???

My WAT theory is: the head gasket failures are from 'Cold Start Knocking', which is 'hydraulic locking' from condensation puddles in the intake manifold, which is horrible for an engine.
With a little bit of: lack of engine coolant changes as called out in the Owner's Manual.

 

Sorry for my late reply to this interesting thread ... i'm a new owner of '12 Prius V with only 25K miles, but am coming from 13 years of problem free ownership with Gen 2 Prius' ('06 and '08). I've read several of the threads dealing with blown head gaskets, gunked up EGRs and PVC systems, etc and would like to add to the WAT theory above with the following speculation:

• High mileage Gen 3 Prius, with short trip history, and/or in colder climates where normal operating temperatures are less likely to be achieved, slowly begin to burn oil as odometer miles grow.
• If ICE does not regularly get up to and maintain operating temperatures to burn off blow-by oil gases and particles, then unburned oil residues start to gunk up the PVC system, excessive condensate accumulates in the intake manifold, and excessive carbon particles start to plug up EGR.
• At some point, oil condensate in the intake manifold may get into a cylinder causing heavy knocking or worse. Alternatively, or at the same time, EGR becomes impaired and fails to operate within design parameters, causing higher than normal combustion temps, creating a perfect storm of knocking and high combustion temperatures.

If this "theory" is accurate, it would be most likely to occur in colder climates with Gen 3 Prius' that are used for short trips. It would also least likely to occur in warm climates, and with "service vehicles" since they would be more likely to burn off excessive oil, even though they have high mileage.

This scenario could also be mitigated or delayed through: frequent oil changes (or switch to synthetics) to reduce ICE wear; installation of a Oil Capture Can to reduce/eliminate manifold condensate; installation of a block heater in cold climates to reduce engine warm-ups; and occasional highway use to increase likelihood of carbon build up in EGR system. The use of an OCC might also reduce liklihood of EGR problems since less oil would be burned by ICE. In other words, the high mileage Gen 3 ICE could start to use oil, but it wouldn't mean that a catastrophic event such as a blown head gasket was inevitable.

The range is now open - fire away!

 

decrease?

 

occasional highway use to increase likelihood of carbon build up in EGR system.

#79StarCaller, Thursday at 9:49 AM said:
decrease?

Yes - thanks.