Advice Needed! P0401, P0300, P0301, P0303 Head Gasket and/or EGR?

With the two cleanings I’ve done, I’ve used powdered Oxi-Clean (mildly caustic laundry additive). For next time, if and when, I’m likely going to this, both for expedience and to satisfy my curiosity:

To one cup water, say in a pint canning jar, add roughly one heaping tablespoon lye crystals. Stir till largely dissolved. Pour into top opening of EGR cooler (bottom opening stoppered).

Prop up securely, leave about an hour, pour out (down drain), flush well with more water, inspect, and repeat as needed.

Note:

Lye is strongly caustic. You don’t want it on your skin, and it will react with aluminum, non-stainless steel, and carbon. Read up on it; use safe practice.

It’s also somewhat hard to come by now. Amazon.ca still has it; not sure about Amazon in the States.

I would only use lye on the EGR cooler. It will react with the aluminum of the EGR valve, and the metal embeds in the intake manifold. The EGR tube between the EGR valve and intake manifold looks to be stainless steel, but it’s relatively trivial to clean with rags/brushes and brake cleaner.

 

A perfect example of a completely clogged totally gummed up cooler that probably should have coded. Typically from an engine that burns oil. The wire method works but the timely repair is to have another one ready to go like you tried to do.

People who clean coolers preemptively don’t really need to do it. But it gives them something to do.

However I would bet my lunch money all this time and expense to date will give you false hope when installed for a maximum of three weeks. Then it’s back to the heart of the problem, oil consumption and a bad head gasket.

 

Besides flow, reduced cooling ability may be detrimental.