Another EGR thread, where the focus is NOT having to clean it, preventative care.

What are some preventative measures, care, maintenance or driving methods to help with never having to clean the EGR?

Techron or Redline SI-1 (PEA detergents)? Using Redline before oil changes and then Techron after oil changes.

Intake Oil Catch Can? What medium is suppose to be used, steel wool?

What’s your take on non-cleaning measures?

For insight here’s what ChatGPT says: (Note it says to use top tier gas because of detergents in said gas and then says fuel additives with detergents wont do anything, which is conflicting information) [Also don’t care what you think about using ChatGPT for car information because its plenty useful in that department as it came in clutch with lots of information and step by step ways of doing my own wheel hubs, rotors and brake pad repair and replacement on my first ever self-repair on a car]


1️⃣ Install an oil catch can (minimal wrenching, no regular cleaning inside the EGR)

• Why: Most of the carbon sludge is oily soot. The PCV valve dumps oily vapor into the intake. Mixed with EGR soot, it sticks like tar.
• A catch can traps oil vapor so less sticky goo reaches the EGR.
• Once installed, you just empty the can every oil change — no need to open the EGR.
• Lots of Prius owners do this. It’s cheap and effective.

2️⃣ Keep oil changes on time (or early)

• Old oil breaks down and increases blow-by vapors → more gunk in the EGR.
• Stick to 5,000-mile intervals instead of 10,000 if you want to be cautious.
• Use high-quality synthetic oil to reduce deposits.

3️⃣ Drive it “harder” sometimes (engine heat is your friend)

• Short trips and babying the throttle don’t help burn carbon.
• Occasionally do:
  
  • Long highway drives (engine fully warm for 30+ minutes)
  • Use “Power Mode” to keep engine running harder — e.g. pass on the highway.
  • Rev the engine up to 4,000–5,000 RPM once in a while (it’s safe, Prius limits redline).
• This keeps EGR temps higher and slows soot buildup.

4️⃣ Use Top Tier fuel

• Better detergents → less carbon in combustion chamber → slightly less soot going into EGR.
• Won’t stop all buildup but helps.

5️⃣ Keep spark plugs, PCV valve, and air filter fresh

• Good combustion = less unburned carbon.
• A clogged PCV valve = more oil vapor in the intake.
• Fresh spark plugs = cleaner burn.

❌

What won’t help

• Fuel additives won’t do much — the Prius EGR clog is mostly oil + soot, not fuel injector carbon.
• “Italian tune-ups” alone won’t fix heavy buildup once it’s started — they just help prevent more buildup.

✅

Summary: no opening, no cleaning



Best real-world combo:

• Install an oil catch can once
• Do regular oil changes with good oil
• Drive longer trips sometimes
• Use good gas
• Keep PCV and air filter fresh

This won’t eliminate EGR clogging forever — but it can easily double or triple the interval before you ever have to clean it.

 

In my head I’m guessing more surface area to catch oil from vapor while letting the vapor free flow through it?

 

Do your catch cans, catch anything and with what medium is used?

Why would it burn oil and at what increments if at all would the worse state Prius engine burn oil?

Block heater but why is that relavant?

What can we consider short trips?

Can we consider hyper milers, people who like to regen brake and coast below 43 miles per hour in auto-ev mode as severe cycle drivers equivalent to short trip drivers? (I’m guessing having the engine turn off and on more than stay on is the culprit with EGR carbon and soot accumulation, sort of like how a torch head will never see soot and carbon if the torch is continuously fed butane in endless amounts with only seeing a flint spark once whereas continuous on and off use of a torch creates carbon and soot on the head inlet of the jet flame from the point of de-combustion of the said jet flame)

Not a lot of people have a chevron gas station in their state, nor data for PEA detergents in their normal gas stations they frequent.

I read redline SI-1 changes the viscosity of oil so it better to use it right before a predicted oil change interval and then techron after the oil change, especially if no chevron around. Theres pictures of redline cleaning carbon off of the engines’ combusting internal mechanisms and surfaces if you search images for it (not for Prius specifically)

 

People dont buy this car as a “spare reliable car” they buy it as their one and only reliable car, no one who is in the latter has time to clean their own EGR while they drive their main car when not working on dissembling their spare cars engine for a whole week. I’m sorry this isn’t realistic. Please do answer the other questions as that is the focus, I know you are the EGR fairy around here but this isn’t the focus.

 

I’ve been researching and it seems, head gaskets will fail no matter how much EGR cleaning you do. The culprit seems to be a bad water pumps failing before the car senses its failing, not giving the driver an engine light code when it needed to before major damage. This car needs too much babying.

 

Watched a YouTube video of an engine specialist “I Do Cars” is his YouTube channel, clown on the Prius engine he was dissecting that had a head gasket failure. The comment section, if you have time points most arrows to water pump causation and the car not giving the driver a heads up of it reaching failure with a in-time engine light other than overheating lights (248 degrees is when it lights up if the water reaches those temps) which is already doing damage by then. Also Reddit comments on this topic are pointing hands at the water pump issue as well. Other than that, 10k mile oil changes will also have a hand in the cause, do 5k instead. Theres proof redline style detergents decarbs most of the internals of the engine and even some passes into the EGR, if your EGR has already a lot of buildup, using detergents will actually make it worse, its a case of using a little early helps a lot later, using a lot late makes things fail faster because it can chip a giant junk of carbon in the EGR and clog it more than it was prior to PEA detergents when the carbon was still sticking to the inner surfaces of the EGR system rather than falling into the free flowing chambers.

 

Which claim exactly isn’t true?

I’m talking about PEA detergents in redline work better the earlier in the cars life you use them, if you use a whole bottle of redline at 100,000k miles you are probably going to dislodge a huge chip of carbon that will do more damage than doing nothing whereas using a whole bottle early in a cars life before an oil change will actually keep the carbon buildup in check before it gets to the build up level of being able to chip off huge chunks from a late life usage of it without any prior use of PEA’s in the cars life. It was a precautionary statement about the use and which way to use PEA’s especially redline because it has 30 percent more than techron but also to specifically use it before an oil change because it changes the oils viscosity negatively.

If this is your only car, you don’t work 5 days a week, have responsibilities or kids to rear then sure dissemble a good junk out of the engine bay, baby bath the shit out that EGR. Meanwhile your average prius driving citizen has no time for that, but they will have time for preventive measures if their lucky enough to still have a prius semi-young enough to start said measures so they don’t have to be stuck with doing a manual cleaning they can’t possibly make or create time for. How much are they suppose to save a year for a professional to do it? Add that to the cost of other car related savings for maintenance they withhold for too.

 

Cool, provide the preventative maintenance history or log of that prius with said 200,000k miles.

 

So why do you tell people to drive up a hill to heat cycle, or things like “lent my sister a car then put fuel cleaner in it” but also why even put oil catch cans if manual cleaning. I have 75k miles on my car to answer your question from before but if you’re going to tell me manually clean it soon, I’m not interested.

Now if you’d like to debate the preventative measures then i’m all ears.

 

So the claims of PEA are snake oil?

What is the restore oil suppose to restore exactly?

let’s not forget all the tools one must invest in to do such jobs, let alone have the mental fortitude to do it all the way without having the slightest mishap shit bricks on your “time allotted to take on this task” with your one and only car.

Yeah just leash the kids to the garage while you’re at it.