Which Fuel Should I Use?

sami_remote · February 12, 2005

I have a question regarding fuel. Is there any advantage in using Super Unleaded fuel (grade 98) on the RX300? I am no expert in the subject but I once heard that Super Unleaded is better for certain engines.

ColinBarber · February 12, 2005

The engine doesn't care which you use. It is designed for 95 upwards. You will get better mpg if using 97-98 RON but you need to use it all the time and will take 2 or more tank to get the full benefit.

If you are doing mainly short journeys the increase in mpg won't be very much.

chib1177 · February 12, 2005

the only difference i could tell by using the 98 ron was that my wallet felt a good bit lighter.

as far as i could tell no performance benefits to my is200 engine

i personally think its a fantastic bit of marketing by the oil companies

jazz_lives · February 13, 2005

Honest John, he of the Daily Telegraph motoring supplement, has two obsessions.

One is engine rattles, which are nearly always caused by the timing chain, and that petrol bought from supermarkets is inferior to that of the same grade bought from petrol stations.

Any substance in his second obsession?

Jazz Lives (and so it does)

ColinBarber · February 13, 2005

Inferior in what way? It has to meet the British Standards test however it is thought that there aren't as many additives as you get from the main oil companies stations.

Bart · February 18, 2005

I used to drive a Subaru Legacy 4-Cam Turbo ( the turbo nutter thing before the days of the Imprezza) and got miffed one day when some 2 litre GT jelly mould thing burnt me off at the lights one day :-( .

I took the car to the dealer mentioning that I was suffering from poor performance and they ran every test under the sun including plugging a fancy box of computerised tricks into a socket that was dragged from under the dash (hot wire style)..."the rally boys tune theirs like” this the technician said…any way to cut a long story short after noting that there was nothing wrong, but agreeing that it wouldn’t pull the skin of a rice pudding (so to speak), the guy asked what fuel I put in it and where did you get it from. Regular unleaded from the supermarket I said – it’s the closest to home!. After he got up off the floor, he advised to use a ‘proper petrol station’ and only use super unleaded. If it didn’t cure the performance I should go back in a week or two.

Needless to say it transformed the car into what it should have been before. I don’t know why or how but I never did take that trip back to the dealer after a couple of weeks! Yes it cost an arm and a leg, but boy it was worth it.

These days I’d like to think I’d grown up a bit and I can’t stand the nagging about pointless extra fuel costs etc…but I still feel there is some truth in the proper petrol and super grade unleaded story – especially if you have a performance car. However, I’d argue that the RX isn’t exactly a performance car (3.0V6 or not)…you pays yer money, you takes yer choice!