Aftermath of Automobile inspection center, when you have D Clean installed

For diesel engine cars, we are required to have cars inspected more often than gasoline cars. If pollution level from the exhaust is over the standard level, then one has to stop driving from that moment on until it’s resolved. The only way to resolve this is to manifold cleaning service (disassemble engine parts and clean carbon sludge out of engine parts. (Especially in the manifold intake area) When car inspection time comes to old diesel car owner, they get stressed whether or not they can pass the tests. For delivery truck owners, suspend their car usage for days are critical to their daily revenue, so this is indeed really a big deal for all diesel car owners.


We often hear from D Clean users that their car got inspected twice because inspector thought something was wrong at first inspection. The reason for this is test results show there is zero pollution output from the exhaust which is literally impossible with most cars. Typically if it’s less than 25%, it means ok but 0% could be quite odd. So they run the tests again to make sure the testing machine is not acting out of normal.

We wanted to check this out by ourselves as well, so one of our staffs got his car inspected recently. Mr. Lee’s car is Santafe 2012 diesel car. His car has 146,000 km since Dec, 2012. He installed D Clean from 110,000 km. So since D Clean installed, he drove a little over 30,000 km. Since D Clean installation, Mr. Lee added D Clean cleaning liquid regularly. In other words, cars should be in great condition. (Almost carbon sludge free status)


Like the test results indicate Mr. Lee’s car showed no sign of pollution from the exhaust. Surely inspector got suspicious about the results, so he ran the test again to make sure the results are correct. Of course, second test showed the same results. We couldn’t know whether or not D Clean took care of NOx as well because car inspection place doesn’t run NOx tests. But from this test results we can assume D Clean might have taken care of it as well.

This led us to think about BMW fire issue again. BMW concluded that the culprit of the fire is from EGR cooler malfunctioning. However they didn’t mention that that triggered high temperature in the EGR valve, and eventually some part of EGR valve got melted. Fire started from this hole. This doesn’t make any sense. How come BMW who supposedly makes reliable car can let this absurd thing happen?



There was no fire incident reported from new BMW car, this means carbon sludge played a key role in triggering issues with EGR valve. And if BMW used metal parts with EGR area, this would’ve not happened. But since they started using plastic parts in the engine  (probably for cutting down manufacturing costs), there was a hole in the EGR valve and it led to engine fire while driving. Even if they’ve used metal parts, if they let carbon sludge buildup like it is today, it would eventually put a lot of stress to DPF part. So automobile manufacturer should consider resolving original problem which is cleaning carbon sludge regularly.


With D Clean installation, diesel car owners don’t need to think about carbon sludge cleaning in the manifold area. If you’re curious about the logic behind it, please see details at this post.

BMW Recall issue

BMW 520D D Clean User Testimonial