Optimax ? - The Unofficial BMW M5 Messageboard (m5board.com)

jimmy01 · 16th October 2002, 02:04

Hi all,
anyone using optimax, I ask as my dad put £20 in his 92 MB190
and it went tits up, missfireing coughing and spluttering, he had to get it drained before driving was right again, anyone had any similar experience`s with it?

M5 powered · 16th October 2002, 02:08

Was it a diesel MB190?

Joking apart haven't heard of any problems either through friends (most have switched to it) or in the press myself.

Regards

M5 powered

jimmy01 · 16th October 2002, 02:11

Hi M5 powered,
But have you used it???
Gonna try in my trusty M535i as all this unleaded is strangling the poor thing, just was thinking about converting with M5 as well
and need some good feedback! thanks.

Mmm-Five · 16th October 2002, 10:18

I have used Optimax for nearly two years and have had no problems whatsoever.

It sounds more likely that there has either been:
a) water contamination in the fuel
b) engine deposits that the detergents in Optimax have removed.

Optimax is basically normal Shell with octane booster and valve lubricant.

Also note that the 98 rating is as it comes out of the pump, and drops to 95 again over time (i.e. a month in a tank). Doesn't matter much in my case as I use at least one tank-full per week, but if you use a small, rural garage that doesn't see many sports cars then their Optimax may well not be up to 98 RON.

M5 powered · 16th October 2002, 13:03

yes I also use it without any problems and overall performance of the engine improved with optimax after the first few tanks.

For me, the most notable benefits for the M5 are a stronger idle (feels alot more positive) and under acceleration. The overall mileage achievable on a tank has also slightly improved owing to the 98 Ron...when driving econmically of course

.

hope that helps.

M5 powered

Kurt Ramsden · 16th October 2002, 13:36

Jimmy,

I agree with the others - I've used Optimax for a while without problems and noticed a smoother idle than with 95RON. Not sure if it's made the car run better in any other way - but I hasn't made it worse. Didn't manage to collect all the Top Trumps cards either - bugger !

MB190's obviously don't like 'performance' fuel.....

Andy G · 16th October 2002, 14:07

I've used it for nigh on a year and a half now, and no probs at all. In fact the improvement in smoothness is quite noticable, and mid range has improved as well.
My son has the tops cards now!!

M5 powered · 16th October 2002, 14:32

I never had these cards you keep talking about. Instead I got a snickers or a mars bar and on one occassion a large carton drink! Yum. Money off would however go down even nicer!

Regards

M5 powered

Lonman · 16th October 2002, 15:22

The problem is that it works too well. For the first few times that you use it, if you have a carbon build up, it will splutter etc, etc.....
It is merely exhaling all the sh1t it has collected over the years and cleaning the engine. All good stuff!

jimmy01 · 16th October 2002, 21:02

Well I tanked up the M535i today so I guess if there was gonna be any adverse reactions I would have known by now!
thanks all, next time its the M5 turn to tank up I will be filling her up with Optimax.