Maruti Suzuki killed off its 1.5L diesel engine due to a design flaw

The design of the DDiS 225 engine made it impossible to upgrade it to BS6 standards.

Maruti Suzuki introduced its all-new DDiS 225 diesel engine in 2019, only to be discontinued a year later. When the BS6 emission norms rolled out in 2020, India’s largest carmaker announced that it would phase out its diesel engines and offer a petrol-only line-up going forward.

This announcement came as a surprise, as it had only been a year since Maruti had started offering the DDiS 225 engine in the Ciaz and Ertiga. It seems it wasn’t the BS6 regulations that killed off this engine, but a design flaw.

According to a media report, the design of the DDiS 225 engine made it impossible to upgrade it to BS6 standards. Besides a dual-mass flywheel, the cylinder head featured an integrated exhaust manifold. This configuration resulted in the overcooling of the exhaust gasses. By the time the exhaust reached the Diesel Particulate Filter (DPF), it turned into a liquid form.

This, accompanied by the soot couldn’t pass through the DPF filter. Also, the regeneration process would reach 1,300 degrees C, damaging the DPF and Diesel Oxidation Catalyst (DOC).

Maruti did consider switching back to a more conventional bolt-on exhaust manifold. However, diesel cars had gotten even more expensive by then due to the stricter emission norms.

Source: Autocar India