EGR Cooler Cleaning (What I learned!..)

I clamped mine to a 4X4 post with a C-clamp.

 

I fitted mine into the drainage at the car wash and while standing to the side, still got hosed.
And after two cycles of the pressure wash, putting the washer tip right into the openings, mine was still mostly blocked.
Soaking again in oxi tonight and then back to the car wash in the morning.

 

My first one was my son's Prius. I used an ultrasonic sprayer. It took about 20 minutes and made a big mess, The second one was our's and I bought a new EGR cooler for that one.

 

You should try easy off oven cleaner. I have used it successfully on my egr cooler and on my 75 RD350 to decarbonize it.
It doesn't have to be warm/hot. Just spray it inside the cooler, both ends. It will foam then turn to a liquid, spray again.
I let mine soak about 30 minutes. I only had to do it once. But I did it twice I think just to make sure.
Then pressure wash. I just used the jet spray on a regular hose nozzle and it cleaned it up nicely.
Mine wasn't near as clogged as yours seems to be so you can do it a few times.
And it's a LOT less expensive then oxy cleanish.

 

Here's my tip about staying dry using a pressure washer:

Grab a one gallon zip-lock bag and cut a slit at the bottom, in the center. At the car wash, or wherever, lay the cooler onto the drainage with the pipes placed through the holes or between the rails to brace it and then place half of it in the bag. Then grab the pressure washer and place it through the hole in the bag and put the nozzle right into one end of the cooler. This way once you've paid and the water comes on you won't have a mess or a hard time getting it in there. Now put your free hand around the hole to seal it and brace the washer then blast away. Anything blowing back will enter the bag and flow into the drain. If the cooler is loose you can move your hand and the bag closer to the cooler so you can brace both at once. While you're blasting it also helps to move the nozzle around row by row to make sure you've gotten all the crud out. You'll see carbon either shooting out the end or running through the bag.

 

Water pump on my Gen 3 went out at 169,000

 

I just did an EGR service yesterday on my 2010 (71,000 miles). It had a good amount of carbon buildup in the system. This particular shop takes the parts from a previous car & puts them in an ultrasonic cleaner for 2 weeks to break it all down. So when the next car comes in, it gets those parts from the last car & the cycle continues. My mpg went from 41 to 49 instantly plus it will prevent a future head gasket problem!

 

What would you guys recommend for someone who can let the parts soak for a good long while? I have access to another vehicle and could park my Prius and soak these for a week or 10 days. Based on how bad the EGR pipe is I am expecting everything to be very clogged up though.

 

soak in gas for 10 days.... then light on fire

 

How about soak in diesel for 10 days then TRY to light on fire.

 

I meant the entire car....

 

Gotcha. Excellent advice - G.ood F.or Y.ou

 

Your welcome..... and the same to you..... : )

 

What’s the miles?

For only the cooler, a caustic, carbon-eating solution will slow-but-sure get it clean. I’ve used oxi-clean. Others like oven cleaner, which is stronger, but you need to use more care. Lye solution, for really clogged case? Straight lye is harder to get now, but AFAIK is still available on Amazon, being a soap making staple.

Disclaimer regarding lye: I’m not sure at what point stainless steel (the EGR cooler composition) ceases to be stainless.

An issue with any of the above: they can’t work if they can’t penetrate; you may need to run wire through the passages, carefully.

Some here swear by pressure washers, saying regardless of carbon build up it’ll blow it out, in 5-10 minutes. Others report a combo of chemistry plus pressure washer did the trick.

For everything else, I’d stick to brake cleaner and brushes, avoid caustic cleaner. The pipe between EGR valve is stainless, but is relatively easy to clean so caustics not needed.

Oxi-Clean solution (Oven cleaners likely similar) requires repeat one hour soaks, punctuated with rinses. You want to get started on it early, then deal with the rest while it soaks.

More info in first two links in my signature. On a phone turn it to landscape to see signature.

 

Oven cleaner and pressure washer.

 

275K and it looks to my untrained eyes that it needs it BAD.

Bought the car from a mechanic last June at 260K miles. This was his sister's car; she put a ton of miles on it doing DoorDash and he seemed to have really maintained it well for her. His own daily driver is a Prius, and he's one of the first to upgrade to Project Lithium. Really knew his stuff. I took it to Toyota for inspection and the only thing they found it needed was new front struts (which you were kind enough to comment on another thread - thank you)

Before I bought the car I specifically asked him point blank about when the last time he cleaned the EGR system and he said "he just did it", and like an idiot I believed him. I should not have taken him at his word. After driving 15K miles and everything seems GREAT, I decided to clean the EGR pipe and it was BAD. Bad enough that my plan is to clean the entire EGR system, intake manifold, and install an OCC.

My current plan is oven cleaner and pressure washer. But if it would be possible to just soak it in a container of parts wash or some other solvent for an extended period and have it come clean, I would do that. Even if it took 2 weeks. No idea if this much crud would ever come off just soaking though.

Thanks again Mendel.

 

Thank you - that is the current plan.

 

With those miles, and totally neglected EGR it’s almost a certainty the head gasket is failing, or has been replaced, or patched with head gasket sealant.

 

Probably going to blow up anyday.

 

Probably going to blow up anyday.

 

Probably going to blow up anyday.

 

What I tell you three times is true.