Does my car really need super premium 95/97 RON petrol?

[Tobias Rideout]

can the vr6 engine run ok with normal petrol. handbook says that I should use super premium/95/97 ron high octaine. is there any long term problems using normal petrol?

[insanitybeard]

I thought regular unleaded was 95 RON, it's the premium stuff that's 97.

[Ben g mon]

I had a vw engined seat Toledo and it was more "urgent" on the 97 RON super unleaded...

[Tobias Rideout]

but does it use more fuel?

[Tobias Rideout]

I thought regular unleaded was 95 RON, it's the premium stuff that's 97.

yeah your right my mistake

[insanitybeard]

I doubt the engine would be any less fuel 'efficient' on the high octane stuff, it's supposed to improve MPG if anything but the extra cost of the stuff over the standard unleaded will more than offset any saving!

[Ben g mon]

Start with the fuel light on then Put in 15 litres say worth of regular 95 Ron regular unleaded, reset trip mile counter on dash  drive normally until used up. Make note of how many miles done
When the fuel light comes on Then fill up with 15 litres of super dooper Unleaded 97 Ron again reset trip mile counter and drive normally until fuel light on and compare the two.

I preferred the 97 Ron petrol as it went like a rocket.....

[Tobias Rideout]

can you mix them both or do you need to wait till the tank is empty? years ago I had a old 94 astra and I think as far as I can remember there was a engine switch for different RON petrol types, is there anything on these engines that you have to do?

[johnnyroper]

It's fine to mix it.

The old fuel injected Vauxhall used to have a ron plug under bonnet for use in deifferent countries as fuel grades varied.

[Tobias Rideout]

ok thanks mate, I want to do a oil change! is it ok to use holts engine flush on these engines?

[johnnyroper]

Purely personal choice but I don't use engine flush I just get oil nice and warm and drain it down leaving sump plug out while I change the filter so dump totally empty. Then refillwith fresh PD oil of decent quality.

[insanitybeard]

Looks like the VR6 motor still uses 5/40 grade oil as the PD's do, but it won't necessarily need to be PD spec oil (505.01) for the V6 petrol.

[Tobias Rideout]

could I use 5w30 oil or do I need to stick to 5w40

[insanitybeard]

I know some of the PD diesel engines (and presumably numerous other VW engines which have a choice of standard fixed interval or 'longlife' service schedules) specified with 5/40 oil for fixed (e.g, 10k) service intervals are specified with 5/30 oil for 'longlife servicing', but unless the 2.8 VR6 engine ever had the same 'dual spec' servicing schedule ever applied to it (which I don't think it did), personally I'd stick to the recommended grade.

[Tobias Rideout]

ok mate.