Catalytic converters and particulate filters are among the most expensive parts on a modern car, and they do not like short trips and slow traffic. This post is for drivers in Singapore and the workshops that service their cars. It explains how these parts get clogged, the signs to look out for, and how the BG CAT/DPF Emission Service helps clean them.

What the emissions system does

After the engine, exhaust gas passes through one or more parts that clean it before it leaves the tailpipe:

• The catalytic converter on petrol cars, or the diesel oxidation catalyst (DOC) on diesels, converts harmful gases.
• The diesel particulate filter (DPF), and on many newer petrol cars the gasoline particulate filter (GPF), traps soot.

A particulate filter normally burns off its soot during longer drives at steady speed, a process called regeneration. Currently, a lot of driving in Singapore is short trips and stop-start traffic, so the filter may not get the chance to regenerate fully. Over time, carbon builds up on the face of the catalyst and inside the filter.

Signs of a clogged catalyst or filter

• A DPF or engine warning light on the dashboard.
• Loss of power, or the car going into a limited power mode.
• Higher fuel consumption than usual.
• Poor results at the exhaust emissions check during vehicle inspection.

Replacing a catalyst or particulate filter is costly. As such, cleaning it while it is still in good condition is usually the more practical first step.

How the BG CAT/DPF Emission Service works

Based on BG Products’ information, the service is a two-step process carried out by a trained workshop with BG’s own tool and adaptors. It is suitable for petrol, diesel and hybrid engines.

• Step 1, BG Emissions System Cleaner (PN PD20): the workshop feeds the cleaner into the exhaust just ahead of the catalytic converter or DOC while the engine idles. The cleaner softens and removes deposits, and is then left to soak.
• Step 2, BG Emissions System Rinse (PN PD21): the rinse is applied the same way to carry away the loosened deposits.
• Burn-off: the workshop then runs a regeneration if the car allows it, or the car is driven at highway speed for about 30 minutes so the remaining material burns off.

According to BG, the service cleans the DPF, DOC and GPF, reduces deposit build-up on the face of the DOC, and helps restore emissions system efficiency and prolong the life of these parts. BG also states that it is safe for catalytic converters and SCR systems.

A note for workshops

BG labels these products for professional use only, with its specified tools. BG also advises a visual inspection before servicing high-mileage vehicles, as removing heavy carbon may expose existing weaknesses in an old catalyst or filter. It is important to explain this to the customer beforehand. Workshops that would like to offer the service can contact us for the kit and details.

Frequently asked questions

Is this service only for diesel vehicles?

No. BG recommends it for petrol, diesel and hybrid engines, including petrol cars with a catalytic converter or GPF.

Can I pour this into the fuel tank myself?

No. The cleaner and rinse are applied through the exhaust with BG’s tool, and BG warns that misuse can damage the engine. It must be done by a trained workshop.

Will it fix a damaged or cracked filter?

No. It removes deposits but cannot repair physical damage. Your workshop should check the condition of the part first.

To have the BG CAT/DPF Emission Service done on your car, visit one of our partner workshops across Singapore. For fuel-side carbon, our earlier post on the BG GDI service may also help.

Sources: BG Products, Emissions System Service; BG Emissions System Cleaner; BG Emissions System Rinse; BG Middle East, Emissions System Cleaner.