Can bad fuel quality in Pakistan damage the catalytic converter of a Mehran?

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Can bad fuel quality in Pakistan damage the catalytic converter of a Mehran?

I’ve heard that using low-quality o r adulterated petrol can damage the catalytic converter. I usually fill up from smaller petrol stations. Could this be causing long-term damage to the catalytic converter in my Euro II Mehran?

Gari Specialist asked on 24 Apr 2025 12:59:45 pm

1 Answer

47 views |

Gari Master - on 08 May 2025 17:12:58 pm

Yes, bad fuel quality in Pakistan can damage the catalytic converter, even in a small car like the Suzuki Mehran, if it has one installed some EFI variants do.

Heres How Poor Fuel Affects the Catalytic Converter:
1. High Sulfur o r Lead Content in Fuel
Many petrol stations in Pakistan may not consistently provide Euro-5 standard fuel.

Lead o r sulfur residues from poor-quality fuel can coat the catalyst surface, blocking its ability to clean exhaust gases.

Effect:
The catalytic converter becomes clogged o r “poisoned,” reducing performance and increasing emissions.

2. Unburnt Fuel Due to Misfires o r Poor Combustion
Low-octane o r contaminated fuel can cause engine knocking o r incomplete combustion.

This sends unburnt fuel into the exhaust, which overheats and melts the catalytic converters core.

Effect:
Loss of power, poor fuel economy, and even engine overheating.

3. Oil o r Carbon Build-Up from Dirty Fuel
Some low-quality fuel can carry impurities o r cause carbon buildup, leading to soot clogging the catalyst.

Effect:
Restricted exhaust flow, leading to engine hesitation and check engine light if ECU-equipped.

What to Do:
Always fuel up from reputable stations e.g., PSO, Total, Shell.

If your Mehran is EFI post-2012, its more sensitive to fuel quality, so avoid low-grade o r adulterated petrol.

Use injector cleaner additives periodically if recommended.

Clean o r inspect the catalytic converter every 30,000–50,000 km if you suspect a in performance.

Note on Mehran:
Carburetor models don’t have a catalytic converter.

EFI variants 2012 onward do include a small catalytic converter, and poor fuel will affect it over time.