Super deep-cleaned EGR cooler: Odd! Is this normal?

What did you use to clean it? Oven cleaner is the fastest and easiest.
It will "eat" the carbon.... It should be shinny, and moving the light around you should
be able to see through each slot.

 

It sounds like you only got the cooler partially cleaned.

Is this the first time you cleaned it? How many miles on the car?

 

Yes as long as you can run brown or blackish fluid out of it every time squirt some water through the other side you see the brown but first runs out until that stops You've got a blob in there I've got two coolers here that will never stop doing that they may never come clean they've been soaking for weeks and days I would have thought I would have ate the metal by now nope

 

Sounds like you’re using some sort of petroleum-based solvent?

what’s the miles on it?

Try a water-based, caustic solution. Corking the smaller end you only need about a cup per session, and 4~5 hour long soaks punctuated by rinses should get it clean.

With light build up of carbon a concentrated water solution of Oxi-Clean Versatile Stain Remover will suffice. For heavier deposits lye solution will be more effective, but use with caution.

 

You need to give it another day or two You really need to not have any brown coming out of it that indicates a clog a big clot sometimes air can help you especially if you've got that clot really liquefied and starting to get in a non-solid state more of a gel state. They get badly blocked and the flow is just about okay at best new or whatever so you want to try and get it super clean 50,000 mi or not because I think can go to rattling very quickly again even after your repair or whatever is going on here Don't push it because this thing will fail on you before you can say jackrabbit.

 

Did you spray the oven cleaner at both ends? Until it was completely full?
Then use the pressure washer?

You may have to get a bicycle spoke or a thin hard wire to clean out the passages.
With that many miles, and it never being cleaned, it will take a lot of work.
You may want to search on duck-duck-go for junk yards for a used cooler.
But if you just keep sraying the cooler with the oven cleaner and let it soak longer,
it will eventually clear it out. Others have had the same issue. You just have to be patient.