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Forum Fuel and economy It says 91 Octane on the bowser but is that really what we are putting in our cars?

sisco01
By sisco01 | Community user | 1 Post | 18 January 2012 at 9:32am

Hi. I have a late model petrol vehicle and the engine is pinking.
I took it into my local manufacturer service agent and was told to use a higher octane petrol fuel.
I work for a company where our fuel cards only allow 91 octane to be charged so this is all I can use.
I have referred to the service hand book and it states that my vehicle must run on unleaded fuel with an ocatane rating of 91 and an anti knock index of 87 or higher.
My question is does the 91 fuel we buy from the pump actually meet these standards as I have heard talk that it might say 91 but in reality it's more like 89.
Does our fuel get regulary tested?
Many thanks

jbiddle
By jbiddle | Community Member | 1657 Posts | 19 January 2012 at 3:12pm

I assume the car is NZ new. If the service book states 91 octane then in theory that is what should be used. A higher octane fuel won’t do any harm however, you end up paying more for your fuel.

Your local Dealer is probably playing it safe by suggesting the higher octane be used. We are aware of some vehicles which are marginal when it comes to the use of 91 octane with engine pinking a result. This is not a reflection of the fuel quality, its more the new vehicle distributor making a call on the recommended fuel octane, possibly a marginal one which could have gone either way.

I suggest you ask the Dealer concerned to make contact with the technical team at Head Office for clarification and to also point out what the handbook is stating.

If they come back and say 91 octane should be OK then some engine management checks may need to be done to determine whether there is a reason for the engine pinking.

It would be interesting to know if the pinking has only been evident in recent times which may indicate a engine management issue.

Fuel quality in NZ is regulated and tested on a regular basis so we definitely don’t agree with the comments made about actual octane values at the pumps. Check out the link below for more information.

http://www.consumeraffairs.govt.nz/for-consumers/goods/fuel-quality-1/fuel-quality-monitoring-scheme