Yes, unfortunately that’s true. A clogged, inoperative DPF / FAP diesel particulate filter or catalyst is a bane for your turbocharger. The opposite can also be the case and this faulty turbocharger will lead to the clogging of the diesel particulate filter.
Failure of one element will cause problems with another. We create a vicious circle. A clogged particulate filter causes a significant increase in the mechanical load on the turbocharger. DPF problems are often accompanied by dilution of the engine oil with fuel, and the turbocharger requires good component lubrication. An engine with a damaged turbocharger gives off more soot, which clogs the slots in the monolith of the diesel particulate filter.
Nowadays, when the automotive world has mastered the fashion for „downsizing” and being eco, it is becoming more and more difficult to meet units without turbocharging or complicated exhaust filter systems. Diesel without DPF / FAP / SRC or naturally aspirated diesels is a thing of the past. As is often the case – additional elements may generate additional difficulties and unexpected costs. The durability of the turbocharger and the diesel particulate filter are interrelated. The failure of one of the elements will sooner or later cause the failure of the other.
A properly functioning DPF / FAP filter catches up to 90% of solid particles, which causes its quick filling. To avoid frequent replacement, the system must be able to rebuild the device. In order for the soot to burn out, it is necessary to increase the temperature inside the monolith, e.g. by additional fuel injection, or use a special substance (cerium oxide) to reduce the degree of heating of the filter necessary to remove carbon deposits. Unfortunately, even such a self-cleaning process is not 100% effective when done properly. There is still ash in the cartridge that has not burnt. As a result of its storage, the DPF eventually clogs. It also happens that active regeneration does not go well – it is simply interrupted or not started at all due to various factors. Then the amount of sludge increases additionally and reduces the efficiency of the filter.
During active regeneration, a dose of fuel is delivered to the inside of the filter to help warm it up. If the process is interrupted, the unburned fuel will get into the engine oil, increasing its volume and reducing its density. Therefore, in some cases (especially in city cars) an increase in the oil level can be observed. Then it should be replaced immediately and go to diagnostics in order to determine the cause of the situation. The increase in back pressure is a lethal factor for the turbocharger. Occurs when the DPF becomes completely clogged and the exhaust gases cannot pass through it to the exhaust.
Effects: – cracking of the turbine seals by gases – blowing the oil out of the rotor shaft bearings, charring its residues – deterioration of lubrication – mechanical damage inside the turbine (blades, bearings, shaft).
How to avoid failure? First of all, eliminate the first symptoms of DPD / FAP blockage, make sure that the process of automatic regeneration of the diesel particulate filter runs properly and is not interrupted. Also, do not ignore glowing lights and pop-up messages on the on-board computer. You can’t wait to solve these kinds of problems. You need to act quickly so that this fault doesn’t lead to more