Head gasket

I'm in the process of replacing one now that failed at 198,000 miles.
It has been brought up on the forum that keeping the EGR system unclogged will extend the head gaskets life.

 

Getting the egr circuit clean isn’t a technical challenge, it’s a bit fiddly and takes about 6-8 hours.

The toughest part is getting the egr cooler out, which there are some difficult to access nuts on the cooler, making this somewhat fiddly.

But for the mechanically inclined, this can be done.

Search around the Gen3 section a bit and you’ll see videos of how tos along with discussion on this very topic. Get after this before it gets after you.

 

"If" the EGR cooler clogging is such a prevalent issue, Toyota (or Mr. Market) should have developed an efficient, in situ, solvent-based "flush" process.

 

At this point, I would be "interested" but not "concerned."

I would probably lean away from letting a dealer do the EGR cleaning, even if you found one that knew what this entails...although it might be fun to see what they would charge and what they would actually do.
See if there's a local mechanic in bean town that's familiar with this and watch a few videos on the subject, especially if I remember correctly about the 120,000 mile maintenance involving spark plugs.

If you drive 500 miles a week the two biggest things that will keep your Prius in the game for extra innings are monitoring your oil levels (every other week in your case) and your fuel efficiency - both of which will reveal early signs of problems if they're monitored regularly.

If you're "coming up on hard times financially" you will need to be much more proactive with your maintenance instead of just handing your keyfob to the dealer and wondering what the bill is going to be.
Read the warranty and maintenance guide and see if there are some things that you can do yourself....like engine and cabin air filter changes.
Also this will help you identify any maintenance items that your dealer might try to sell you that are not needed or even listed in the schedule of maintenance.

Finally, read up on some oil catch can posts and about 15 threads on transaxle fluid changes.

It will take a little bit of time, but this will be better in the long run than paying for maintenance that's not needed or (worse!) not paying for maintenance that IS NEEDED.

Good Luck!

 

Not aware of any, no. All seems DIY, which suggests low incidence.

 

I drive 400 miles a week and 95% of it is highway. Guess what still gets carbon deposits .

It’s just a function of the technology .

Good luck and keep us posted .

 

I priced an egr cleaning at the dealer, which for them is replacing the egr cooler. It was almost $800. The retail price of the stainless steel cooler is over $300 and the access is tough. That price does not include an egr valve. The cooler is an elaborate stainless steel water cooled module which has exhaust gas "radiator" channels inside. The unit flows hot exhaust gas from the exhaust manifold to the intake, under control of the egr valve. Those channels get totally clogged up with gummy carbon. I had a local mechanic do mine which allowed for a convenient intake manifold clean and a new pcv valve. Its a job because a lot of the engine compartment is removed and small hands are a plus. The part is about 1/2 price on ebay. I would think twice about buying a used cooler unless it was pre-cleaned.

 

Given it's stainless and relatively speaking a PITA to R&R, it begs for an in situ solvent flush sort of fix.

 

Does anyone know if the cooling channels go through the middle of the unit? I'm wondering if you could just drill a quarter inch hole right through the middle - yes, it might effect emissions on startup in cold weather...

 

The smiplest way to see where you're at, is to check the degree of carbon build up in the EGR pipe, a stainless steel connecting pipe between the EGR valve and intake manifold. Watch @NutzAboutBolts video #16 here:

Nutz About Bolts Prius Maintenance Videos | PriusChat

Two or three other videos linked there too, for the full cleaning of the intake manifold, full EGR clean, and Oil Catch Can install.

Good thread:

EGR & Intake Manifold Clean Results | PriusChat

Another:

Oil Catch Can, Eliminate that knock! | PriusChat

Somewhat tools worth having:

E8 Torx socket (mandatory)
E6 Torx socket (optional, but good to have, to remove the throttle body studs from intake manifold)
3/8" ratchet wrench, regular and long handle, flex head, you can never have enough
1/4" ratchet wrench, or 3/8" to 1/4" reducer
Ratchet extensions: you can never have enough
Long needle nose piers, straight and bent tip
Ratcheting 12mm box wrench (optional, but makes disconnection of the EGR cooler from exhaust easier)
Torque wrench (3/8" and 1/4" both good to have)
Floor jack and safety stands (or ramps): basically some method to raise front, if you need to take underpanel off, which you may need to, both for access and to recover dropped items.

 

The exhaust channels terminate at angles so the drill bit has to bend.. However chucking up some solid wire and feeding it through each channel can work after a couple of days of soaking in parts cleaner. Probably the fastest way is to buy a new cooler on ebay for about $150, swap the old one out and then carefully clean the old unit to be ready for the next time, or sell the cleaned unit on ebay.

There is also a cleaning service where they actually give you a clean unit for a price plus your core. Essentially remanufactured. Toyota Prius EGR Cooler Cleaning Service | eBay

 

That 'cleaned' photo doesn't look particularly compelling.