EGR Cleaning

I used oven cleaner. Run whatever product you use through a quality ai.

Also more important than the cooler, clean the egr passages on the intake manifold. Special attention on cylinders one and 2

 

You want to make as sure whatever products you use are 1. Effective and 2. Don’t damage the material.

 

The cooler is stainless steel. Accordingly, I would recommend:

Put rubber stopper in the the smaller of the two end holes. It’s roughly 21 mm inside diameter, and a #4 stopper is suitable. This allows you to prop up the cooler, say in corner of laundry sink, and pour in just enough cleaning solution (takes about a cup), and let it soak.

For solution, I’d recommend a water based caustic cleaner, 20% (by weight) potassium hydroxide (KOH). AFAIK that chemical is still readily available in the States, being a component of DIY soap making. And it’s actually a bit more effective, say compared to sodium hydroxide (NaOH). The latter is used in oven cleaner and drain cleaning products, but is difficult to buy now without a licence, due to being used to produce meth.

anyway, cork the cooler, then (carefully, with appropriate precautions) mix the solution, pour it in, prop up the cooler in corner of laundry sink.

after about an hour, pour it out, rinse thoroughly, repeat as needed. After each cycle inspect with a good pinpoint light source, till you’re seeing virtually no carbon, just clean/bare metal.

if the cooler is clogged to the point that solution can’t even penetrate, gently working a wire through helps.

Have a look through the EGR links in my signature (on a phone turn it landscape to see signatures), for tips, tools, workflow.