ISLAMABAD: The Oil Compa­nies Advisory Council (OCAC) — a representative body of around a dozen oil marketing companies (OMCs) and refineries — threatened Honda Pakistan on Wednes­day to withdraw its complaint about the alleged sale of low-quality fuel in the market or face legal action.

But OCAC’s difficulties appeared to have been compounded by question marks raised from within its ranks when one of its key members – Hascol Petroleum – also supported Honda’s allegation of high manganese content in petrol and asked the government to upgrade fuel quality in the market and subject fuels to stringent standard checks.

In a complaint to the Oil and Gas Regulatory Authority (Ogra), Honda Atlas Cars Pakistan reported high manganese content in recently upgraded 92RON (Research Octane Number), causing three major issues, namely catalyst blocking or chocking of the catalytic converter, engine knock due to low octane quality fuels and adverse human health effects of manganese and specifically blamed three leading OMCs – PSO, Total and Shell. The complaint said the car manufacturer had to suspend its latest variant 1.5L Turbo VTEC car due to the substandard fuel quality.

An OCAC official said Hascol was trying to cash in from badmouthing three largest OMCs for a higher market share even though its entire fuel supplies in the market were of the same origin and quality standards. He said the OCAC would deal with Hascol internally.

Contrary to the impression created by Hascol, OCAC clarified that fuel being sold in the country is strictly in accordance with the approved specifications issued by the Ministry of Energy, Petroleum Division. This is also a fact that “all OMCs, including Hascol, import and buy petroleum products from local refineries in accordance to the official country specifications. Therefore, petroleum products being sold by all OMCs are on exactly the same specifications across Pakistan,” it said.

The OCAC said the most likely cause of any observed catalyst blocking was a faulty engine management system or high sulphur fuels. Sulphur in fuel is damaging to catalytic convertors; it will poison catalyst surfaces, reducing the efficiency of the catalyst and sulphur compounds (sulphates) can block catalyst substrates.

It said Pakistan was currently at the beginning of its clean fuel journey and sulphur levels remained higher than those required for Euro-IV vehicles, such as Honda Civic 1.5L VTEC Turbo referenced in the complaint. The quality of the fuel in regard to preventing engine knock is measured by the octane value or RON of the fuel.

Based on the specifications of the VTEC turbo vehicle, 91RON fuel is recommended. It means the vehicle is calibrated to operate on 91RON fuel but has the capability of compensating for lower octane fuel. If this vehicle is operated on less than 91Octane (regardless of the source of the octane improvement), it will knock. This knock will be detected by the knock sensor, and the ignition timing will be delayed to prevent engine damage. If the knock sensor malfunctions, the catalyst plugging may actually be caused by the engine knocking, the OCAC explained.

This scenario is particularly likely in Honda Civic 1.5L VTEC Turbo model, which is both high compression (10.6:1) and turbocharged, while the other models that presumably have not experienced field issues are both non-turbocharged and lower compression (9.7:1). The fact that sales of this vehicle were to be suspended may suggest that the vehicle manufacturer was aware of this and intended to properly calibrate the vehicle for the local market, and was attempting to blame any catalyst failures and potential warranty claims on fuel quality rather than on the inappropriate calibration of the vehicle.

The OCAC said octane can be improved by a number of means, including the use of high-octane blending components, increased refinery severity, oxygenates, or additives. As long as a fuel meets the required octane quality and the vehicle is properly calibrated for the region, it will not cause engine knock.

It said Methylcyclopentadienyl Manganese Tricarbonyl (MMT) was surely a manganese-based fuel additive used in the production of unleaded fuel to enhance octane. It was also used in lead replacement as it was the only octane-booster additive, which enables old car engines to run with unleaded fuel. By using MMT, refineries can reduce the use of benzene, aromatics and olefins, hence lowering more internationally recognised harmful-to-health chemicals. Benzene is a known carcinogen.

It said the MMT use in Pakistan was started by refineries over 10 years back after extensive due diligence and ascertaining that both the US Environmental Protection Agency and an independent European Union risk assessment had confirmed that the use of MMT as an octane improver in fuel would not cause adverse effects on human health or the environment. MMT dosage is restricted to the prescribed limits.

The OCAC alleged that Honda Civic 1.5L VTEC Turbo model was currently incompatible with market fuels available in Pakistan because it was a Euro-IV vehicle in a market where sulphur levels were currently unsuitable for this emission standard.

Secondly, the engine management system of this vehicle was improperly calibrated for the Pakistan market and manganese was extremely unlikely to be the cause of failure of this vehicle. In contrast, Euro-II vehicles present in the market also have catalytic convertors and were not reporting such issues. Reports that a Honda “team from Japan was replacing the software used in the 1.5L VTEC strongly suggests that the problem is not fuel-related but because of an incompatible vehicle emission management system”, it added.

An OCAC official said there is no limit on manganese content in the government’s standards for petrol.

Published in Dawn, November 9th, 2017