My EGR/OCC Anecdote

I wonder how clean and how long EGR cleansers and other techniques other than mine produces a fully clean EGR cooler.

When I was cleaning mine, I was not worried about leaving a "film" inside the EGR cooler. I was more concerned about the thick and possibly "flaky" deposits left behind that might come off in service and find itself in either the EGR valve, go through the intake manifold and into the engine. With ultrasonic cleaners that apply force to the deposits, there is a possibly.

Based on this case, I believe the time and work to get the EGR cooler fully and "squeaky" clean was worth it.

On that account, dealers will do no less than to install a new EGR cooler.

A check of eBay now compared to a few months ago reveals that price of a Gen 3 EGR cooler has risen, as the issues with the coolers' clogging has become readily apparent. Likewise, the number of listings of offers have declined.

Still, as I did, the prepared owner of Gen 3 Prius models should buy one, clean it fully, and keep it stored away in anticipation of needing it at the 100k mileage. With replacement, the newly removed EGR cleaner can then be cleaned and stored. With the demand ever increasing for used ones and Gen 3 cars increase in mileage with age, the used coolers will likely be in demand for years and will not likely become useless for many years to come.

Time will tell if and when Gen 4 EGR coolers may also become an issue.

Finally, fully clear liquid after a one week long soak with solvent, is the only way to tell that the cooler is completely clean.

 

Vibrations and cleaning solvents might loosen but not completely dislodge the particles. These clumps might inadvertently clog the components downstream.

How is complete cleaning not an advantage?

Like medical heart operations, damage can occur in the future by loosened plaque as the result of the operation.

I prefer taking extra time to get it completely clean.

 

Remember that the cooler will clog again.

I don’t strive for “eat out of it” clean, but “clean enough”.

After 10 minutes with the pressure washer, 99% is the level of clean you get.

Could I run Brake Kleen through it and get the residue out: yes.

Will you have to do the cooler with some frequency: yes

If I put the cooler on a replacement frequency along with the engine coolant, I get it attended to before it is an issue .

Something to consider .

 

Not worried about the natural progression of the EGR cleaner slowly building up tp a clog. I am worried about chunks flaking off of the disturbed previous clog.

 

"Flakes" are not going to come off. If it take a cleaner and a pressure washer to get it cleaned off,
a few pounds of pressure are not going to brake them free. If it would, they wouldn't be a problem and
wouldn't need to be removed to be cleaned.
You could clean it out the same was you clean out injectors on a diesel, low gear and high rpm's.

 

I was gonna settle for clean enough, after dumping a full can of brake cleaner through it:





then tried @mjoo oxi-clean solution:





and that was the magic bullet:



Go to the light, Luke:





The patient:

 

My son, Lucas was born this May 4th and that's his favorite pastime (looking at lights). He'll probably grow into an astrophysicist or Jedi warrior.

Pixel XL ?

 

I still prefer absolutely clean.

There is nothing like absolutely clean or NEW condition,

 

As @Mendel Leisk said....Oxi Clean does a wonderful job. I've done this twice and it got both of them squeaky clean.

 

That's how clean my cooler looked after using gunk and oven cleaner....

 

There's many ways to skin a cat. Pick your poison

Pixel XL ?

 

But, there is only one absolutely clean of carbon, with no matter to how you get there.

 

I think oven cleaner is on the same side of the basic/acid spectrum as oxi, albeit a little more caustic. I did try it on the intake manifold. I could never get it squeaky clean though, due to coarse interior plastic I think.

 

I wouldn't use oven clean on the intake! It's plastic! It could eat it!

 

I prefer mine dirty.

Cleaning yet to be done.

 

So's the oven cleaner bottle. Pretty sure it's ok.

 

Bottle? Mine is in a can.
I guess it's like Gunk. They make a foam can. Which does NOTHING to remove grease and oil.
Then the original Gunk, WILL remove grease and gunk.

 

I'll admit that at the time I was scared off by oven cleaner. Thought it might be a little too harsh. However, glad to see people here are having success with it!

 

I like to think about it as - every hot oxiclean soak that removes gunk should buy me another 3k-5k miles of cooler life.

Also any coating of carbon will insulate the cooler reducing it's heat removing ability. One of the SAE studies I read mentioned the carbon having the same R value as styrofoam.

Pixel XL ?