Misfiring has led to the complete destruction of catalytic converters and more specifically their ceramic inserts. What does not burn in the cylinder chamber will burn up in the catalytic converter damaging it. It could be fuel with leaking injectors or ignition loss or it could be oil with an oil defect. 

The cartridges did not look bad while the computer reported a low catalyst efficiency error on two banks so four cartridges to be replaced. By the way, I will mention that the indicator of wear and tear of catalytic converters is not always their appearance, they may look very good and may no longer work as a result of natural wear of the precious metal elements contained in the catalytic converter cartridges as was the case here. 

The catalytic converters already came to us empty so I'm skipping the brooding about what and how and why because the causes of wear or damage to the catalytic converters could be many. We measured the cans of catalytic converters and flew for the cartridges we had on the shelf. The 130 mm diameter  80 mm high cartridges turned out to be ideal in terms of fit. Of course, they were also selected according to the relevant emission standard and capacity.

For the relatively low mileage, the catalytic converter is very damaged. At first I thought it was an oil defect, however, the culprit turned out to be a leak in the exhaust manifold, which on this model is liquid-cooled and connected to the head by water channels, in addition, it is integrated with the turbocharger as a whole. 

Ours were here... ;-) The customer brought catalytic converters for regeneration, which he had already had for regeneration about 2-3 years ago.

6 year old car with defective catalytic converter? Impossible, probably the probe is failing.... We will change the probe and it will be git. Probe replaced and still the same thing. I often encounter such a situation, I warn against hasty replacement of probes, supposedly the easiest, fastest, maybe it will work. Unfortunately, in most cases probes are replaced unnecessarily. Then the catalytic converter goes to me for replacement of the cartridge.

In today's article, I would like to touch on the subject of catalytic converter regeneration for BMW E39 540i V8 car. I recently had the opportunity to perform such a remanufacture, and today I will share with you information on this subject.