Fuel quality

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gzt

10947 posts

Uber Geek

# 205528 16-Nov-2016 21:07

Fuel quality in NZ. I've seen this mentioned in different discussions but I'm not understanding the full picture.

How does fuel quality differ between stations and/or brands and what are the effects on vehicles?

Fuel quality is completely different from octane. No problems understanding that part! Having said that, I'm aware that different methods of setting/maintaining octane may have an effect on quality independent of octane so feel free to comment on those.

Batman

Mad Scientist
21096 posts

Uber Geek

Trusted

Lifetime subscriber

# 1672407 16-Nov-2016 21:30

I heard from someone that the 91 fuel is all generic, whereas premium fuel has brand specific additives (mainly detergent). if you want/need 98 then there's only one choice :)

Involuntary autocorrect in operation on mobile device. Apologies in advance.

k1w1k1d

625 posts

Ultimate Geek

# 1672431 16-Nov-2016 21:59

As far as I know most fuel companies use the same base fuel from bulk tanks in each city/town.

Company specific additives are automatically added when a tanker is loaded with fuel from these bulk tanks.

richms

22626 posts

Uber Geek

Trusted

Subscriber

# 1672434 16-Nov-2016 22:04

Anything but gull is my fuel choice.

Richard rich.ms

scuwp

3214 posts

Uber Geek

# 1672451 16-Nov-2016 22:29

One person supports this post

Petrol goes in, car goes brummm, job done. I doubt there would be any measurable difference for normal road use.

Always be yourself, unless you can be Batman, then always be the Batman

lNomNoml

1376 posts

Uber Geek

# 1672470 17-Nov-2016 01:16

I've noticed according to my logbook that I generally get more mileage from BP fuel than anyone else, we are talking around 20 / 30KM's

BruceHamilton

77 posts

Master Geek

# 1672475 17-Nov-2016 03:56

Just a few points about NZ Petrol. It has to meet minimum quality and performance specifications as detailed in the government regulations. However, engine technology has developed significantly over the last 20 years and government regulations have struggled to keep up. One major issue is the additive packages, specifically deposit control, that are not specified in regulations. As fuel injection technology developed oil companies modified their formulation additive packages to provide more aggressive deposit control ( engine cleanliness ) management, however the US EPA wanted to reduce metals, active suphur, and detergents to help emission control technologies, and intoduced regulations in 1995.

One consequence was that some additive packages had to be reduced, and deposits formed in injectors, inlets and combution chambers, and valves were prone to stick. The EPA was not keen on changing regulations, but was planning on more strict emission control that would require more aggressive fuel cleanliness standards. In 2004 some auto companies and oil companies came up with a new standard called " Top Tier " using fuels based on the Worldwide Fuel Charter for petrol. To qualify, the fuel had to pass more stringent engine cleanliness tests using an 8 - 10 % ethanol fuel - which is more demanding than hydrocarbon fuels.

The approved fuel does not have to contain oxygenates such as ethanol, only the test fuel. To pass, a fuel required around 3x more additives than EPA required, but they still had to be metal free and comply with EPA performance and emission requirements. Also the fuel company had to meet the standard on all grades of petrol sold in the national market ( Antiknock Rating ( USA ) or octane rating ( rest of world ) ), but higher octane grades would often have higher levels of additives, reflecting the more onerous requirements of higher performance engines.

Not all engine manufacturers joined, but Toyota, VW, GM, Fiat Chrysler, Honda, BMW, Audi, and Mecedes-Benz joined ( notable omissions included Ford, who recommend BP in the USA ) nor did all oil companies, Shell and Mobil did ( BP didn't, but claims specified products exceed the specification ). However most companies developed additive formulations ( or purchased petrol additives from specialist suppliers such Lubrizol, Techtron, Amoco, etc. ) and also modified the fuel hydrocarbon composition to meet the more stringent EPA emission requirements on modern engines and also exceed "Top Tier" requirements.

What we are seeing in NZ is the introduction of the new fuel hydrocarbon profiles and additive technologies to cope with the more stringent requirements of modern engines. With common industry storage at smaller ports, the extra additives are conveniently added via in-line blending at rail car or road tanker despatch. The base fuel already has additive packages needed to meet NZ govt and industry specifications, but they may no longer satisfy all imported vehicles, hence companies are promoting their extra packages.

As noted earlier, higher octane fuels tend to have superior additive packages or more of the package. The main effect of effective deposit control is improved engine performance, which is reflected in improved power output and fuel economy. Regardless of contrary anecdotal "evidence", current premium fuels do offer tangible benefits to consumers. Buying a "brand-name" petrol is more likely to include the extra additives, but it's always your choice if you don't want to trust multinational oil companies.

MikeAqua

5385 posts

Uber Geek

# 1672525 17-Nov-2016 08:54

Ethanol is something to watch out for. It causes significant problems for boaties in the USA. Ethanol absorbs water, and if you have a car that you refuel infrequently, particularly in a humid environment you can have issues.

Mike

Scott3

614 posts

Ultimate Geek

# 1673212 17-Nov-2016 22:45

One person supports this post

MikeAqua:

Ethanol is something to watch out for. It causes significant problems for boaties in the USA. Ethanol absorbs water, and if you have a car that you refuel infrequently, particularly in a humid environment you can have issues.

Ethanol is not intrinsically "bad", but a lot of Gull's bad rep come from people running their E10 (10% Ethanol, 90% petrol: 98 octane) blend in incompatible engines (or where it has brought to light issue that were dormant with pure petrol, such as excessive water in the tank).

Avoid it for older (10 - 15 year+ old) cars, and small engines such as lawnmowers.

MikeAqua is correct, ethanol blends absorb water. Even though our outboard is compatible with a 10% ethanol blend, most boaties avoid ethanol blends due to the heightened risk of getting water in the fuel in a marine environment.

I have no concerns with putting E10 in my (10 year old) car.