VR4 Petrol >> 96 or 98?

[Ultra VR-4]

Hi, I was told by a friend that you cannot simply change petrol from Premium unleaded 96 to 98 and so forth...??
Is this true? As only Mobil & BP seem to sell 98... and even then only some mobils sell synergy 8000 and BP's Ultimate...

[Nick VR4]

The only issue will be is the ecu will compensate for lower grade full and adjust timming etc
I have had to use 96 got stuck somewhere on fumes
Filled up half a tank and them mixed 98 with it
Didnt notice to much difference to be honest
But I always use 98 now an 98 is recommended for VR4

[Brind]

Our basic fuel is 95 RON but we can buy super unleaded which is 97RON we also have Shell Optimax which is Shell's own brand that is meant to have cleaning agents in it and all that which is 98 RON which is the highest you can buy here.

My car was running on 95, either by the dealer or the previous owner, I've been using the higher octane Optimax.

The ECU was reset today by a Mitsi dealer to check a fault with the AYC and the car goes like a rocket!!!!!!!!!!!!!!
Apparently if the car is running on lesser fuels or a dodgy batch your ECU will go into safe mode and reduce your turbo boost perminantly! you have to reset your ECU after this has happened.
If the ECU goes into safe mode you can lose 60bhp or more easily!

[Ultra VR-4]

Hi, thanks for the comments but what is ECU?

[Brind]

The ECU is your engines electronic brain.

It controls your spark plug timing, all your engines sensors are attacthed to it to enable the engine to run correctly.

[Brind]

Disconnect your battery for a while or remove the fuse that corrosponds with the ECU for a while.

Then the ECU forgets what it has learnt and will re learn.

[haydar]

Originally posted by Brind
Disconnect your battery for a while or remove the fuse that corrosponds with the ECU for a while.

Then the ECU forgets what it has learnt and will re learn.

How do you need to leave the battery out for. Also, what is the label for the fuse that controls the ECU?

[Brind]

Read this thread: http://www.clubvr4.co.uk/forum/showt...=&threadid=290

[BraindG]

ignore the rather extreme 30 minutes comment.. something more along he lines of a minute would suffice