Prius Gen 3 Major Maintenance: EGR, manifold, spark plugs, Oil Catch Can

My preference, if going to all that trouble, may as well drain and refill the engine coolant. Same amount of work. He just bought this car with 100K miles and the coolant has probably never been replaced anyway. Just as he’s replacing the spark plugs.

I agree with replacing the rubber gaskets but not the metal gaskets.

 

We'll agree to disagree, on the coolant?

Honestly, it was very easy.

 

Both coolant?

 

In these procedures, you only touch the engine coolant, not the separate inverter coolant.

One jug of coolant was enough for the engine coolant but I think you’ll need a second jug for the inverter coolant, even though it’s far lower capacity than the engine coolant. Unlike the engine coolant, the inverter coolant fills up very fast and it’s easy to over fill and make a mess if you aren’t careful.

Both coolants are due at 100,000 miles-ish and if you jack the car and remove the pan for the engine coolant you may as well do the inverter coolant. Make sure you don’t confuse the inverter drain plug with the transmission drain plug.

Good luck. Wish I was nearby to help you.

 

Update on post OCC and doing the spark plugs

still not quite getting the Mpg I had before and some burning smells. While investigating that, after 1000 miles there is about 3 tablespoons of oil in OCC and still quite a bit pooled in the intake manifold. I think I will put some more steel wool in, hopefully it will catch more oil before it pools in the manifold.

 

Also just did a successful head gasket job on my other 2011 Prius if anyone in the Northern California Sacramento area needs a hand, it’s helpful to have another person

 

Steel wool? Bad YouTube info reared it’s ugly head in here again.

 

Which CEL codes were thrown prior to head gasket job?

 

Cyl 1 misfire (spark and coil functioning perfectly) + fuel/air ratio issues
Other signs: lowering coolant even after continuous topping off
Lowering mpg ~38
Eventually led to the obvious signs: white exhaust smoke (visible if you shine a light at muffler) and heaving knocking noises on startup

 

What’s the better alternative?

i said “wool” but what I use is the SS dish scrubbers, 2 for $1

 

I’m only going to warn you to be CERTAIN that no small bits of steel can break loose. The system is under vacuum and small bits of stainless steel drawn into your engine can damage or even destroy it. Stainless dish scrubbers aren’t built to very high quality standards.

 

Maybe some thin gauge bare copper wire, bunched up?

 

I used them for 30k miles and they were fine.

How often do you find little bits of them in your dish water?

I've not seen them disintegrate and that's with a heavy application of force.

And all they are doing in the catch can is sitting there with spooge collecting on it.

Save the hysteria for politics.

 

Back to the EGR system, I stopped following PriusChat for a few years, so missed the evolving EGR issues.

Now, my 2010 Prius has 174,000 miles, but has no symptoms, except my mileage is down about 6 or 7 mpg from OEM, at around 46mpg, per the computer. In other words, no oil burning, or noticeably rough running, or DTCs.

I have time to work on the car, which will become my son's. What approach would folks here recommend? Perhaps start by taking the EGR system apart, and seeing how things look, as a first step?

 

The simplest 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

Some 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 (or 1/2 plus reducer)
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.

 

Also good to clean the throttle body. There's another @NutzAboutBolts video on that. I'd recommend to unbolt it, pull off the electrical connector and lift it right off, for more thorough cleaning. No need to disconnect the coolant hoses; they have enough play that you can lift it up, flip it over and tie it off, suspend it from something adjacent if needed.

Have a look at the swamp below, in the intake manifold; that's where oil catch can will help. There will be a lot of gunk in the intake, it's really part of the EGR as well, has EGR passageways that need cleaning.

Also, down at the bottom the MAP (Manifold Absolute Pressure) sensor lurks, probably oil-drenched. By your miles, maybe getting crusty? CRC MAF Sensor cleaner (spray can) is good for that, basically a very clean electrical-contact cleaner.

Torque values for the throttle body bolts/nuts in one of the attached above.

 

If it’s certain that no small bits of steel can break loose then it’s safe to use.

 

Thank you for the Repair Manual sections, Mendel.

I pulled my EGR tube, and have attached photos. Things don't look too bad, in my opinion, at 174,000 miles. The first photo is from the side at the EGR valve, and the carbon deposits are mostly right at the end (these don't run the length of the pipe. The manifold end is slightly oily.

Any comments?

 

The EGR valve and cooler need a cleaning visit. And the intake manifold. Don't doubt it. You're on the outskirts of head gasket failure city.

This is what the EGR cooler interior will look like, all the way through:



You can barely slip a thin gauge wire through the EGR cooler, that's how tight it is. The EGR cooler and valve will have similar crusties. And the intake manifold EGR passageways, same story.