Scratch

iTrader: (1)

OK - just been on a bit of a jaunt down through France to just south of Paris. Noticed something with the MY98 (standard other than scoobysort decat centre and PPP back box).

Have always run the car on 95 Ron unleaded over the 15 months I've owned it.

Came fitted with a boost gauge, which has always read ~10psi on full boost prior to the exhaust change (about 4-6 weeks ago), then typically 11psi held, with peak 12-13psi

Now on this trip having filled up with Shell 95 Ron unleaded in France, then subsequently with Total 95 Ron, the car has been running higher boost. I have peaked at over 1 bar, max was 1.02bar from the turbo timer reading, showing 16 psi peak, 15psi held on the boost gauge (in 4th and 5th gear) and 12psi held in other gears.

Now got UK Esso 95 ron unleaded in it again now and it's still peaking higher than normal at 13-14psi, and holding at 11psi again.

Is this just coincidence or is this fuel related ? (If I put 98 ron/optimax in will I see the same increased boost levels in the UK - is this step change normal behaviour for a fuel grade change? does the ECU learn this quick? Could it be that it's also now finally worked out the exhaust change ?)

Any answers/suggestions ?

[Edited by Scratch - 4/24/2003 7:15:44 PM]

GBruce

Scratch,

My my98 with full decat would peak at just over 1 bar and hold about 0.9, perhaps a bit less in warmer weather or after sitting in traffic for a while. The boost sounds about right, sounds like it has just taken into account the change of exhaust.

George

Scratch

iTrader: (1)

Yeah but that doesn't explain why it has gone back to 11psi held with 13psi peak now I'm back in the UK on UK 95RON fuel.