wrong fuel

[bezza911]

I just made a huge mistake I think, I put some 98 instead of 95 here in France. Car is running like a pig now. Love revs it just wants to die, keep the revs up at 2000RPM and it was OK to get it home. What damage have I done, or can I run the 98 through on a highway blast this afternoon, or should I cyphon it all out and get the 95 back in there???

I used to do this on an old Lancia I owned everyonce and a while, used to "clean it out" as my mechnaic told me, maybe not so good on a porsche 911, what a twat I am!

[twistoffat]

Bezza, I would have thought the problem is with cars tanked with lower octane. I wouldīnt have thought the higher octane would cause a bigger problem. Sounds to me like you got dirty petrol/gas.
You could always try change the the fuel filter. I got some dirty gas a while back which caused low rev problems.A quick hig rev blast seemed to correct it. I put in a new filter and it was gone

[bezza911]

Hi Twist,
well I am wondering if the overfill may have caused the issue, it appears to have eased a little on my journey back from boulangerie just then, but I am now working my buns off on board a yacht and will not get to check it out again til this evening.

I will be back,

Thanks,

Bez

[Drisump]

What "overfill"? Those octane numbers are only dreamed about in these parts. Even though I have no idea what type of car that you have, I would think that if there is enough demand in France for 98 to be commonly available, that 911's would work on it fine. (since 911 Euro's are quite highly tuned). How empty was your car upon filling? If you were almost empty you may have stirred up the debris that resides in all tanks after a number of years. If you didn't push the limits of the tank, I'm thinking that either you've picked up bad gas or the problem is unrelated. Cheers

[hessel1974]

Using a higher octane instead of a lower octane should not influence the performance of your 911. The other way around it can when your engine has not been fitted with the harder outlet valves. the Car might pull a little bit less if it is a lower compression car, but certainly not stalling.

Depending on the year of 911 you drive, Porsche's have always been higher octane cars than others, so it would reallty surprise me if this caused any issues.

What year is your car??

[flatsixjunky]

bezza911,

What kind of 911 do you have? I have an '89 Carrera with an 98 octane SW chip and it runs like a dream. The higher octane is not your problem. Like the others have said, maybe dirty gas, fuel filter, injectors, it could be a lot of things.

[schumicat]

octane is measured differently in Europe. 98 in Europe is something like 93 in US. Higher octane does make gas harder to ignite, so it is possible I guess that too high octane could make it run poorly but it seems unlikely (it'd be common to have problems running too low octane). did you put leaded gas in?

Originally Posted by Drisump

What "overfill"? Those octane numbers are only dreamed about in these parts. Even though I have no idea what type of car that you have, I would think that if there is enough demand in France for 98 to be commonly available, that 911's would work on it fine. (since 911 Euro's are quite highly tuned). How empty was your car upon filling? If you were almost empty you may have stirred up the debris that resides in all tanks after a number of years. If you didn't push the limits of the tank, I'm thinking that either you've picked up bad gas or the problem is unrelated. Cheers

[andyt11]

exactly. see extract from web that explains better than i could.....

In most countries, including all of those of Australia and Europe the "headline" octane rating shown on the pump is the RON, but in Canada, the United States and some other countries, like Brazil[4], the headline number is the average of the RON and the MON, called the Anti-Knock Index (AKI, and often written on pumps as (R+M)/2). It may also sometimes be called the Road Octane Number (RdON)

the whole articale is here...
Octane rating - Wikipedia, the free encyclopedia
and goes on to show all the fuels commonly available and how they are marked differently in different places.

Getting back tot he original question, someone must be able to advise what the consequences are of putting fuel in that has too high an octane reading? 98 RON fuel over there looks like it would be labeled as premium 93 octane here in north america.

[twistoffat]

Originally Posted by schumicat

octane is measured differently in Europe. 98 in Europe is something like 93 in US. Higher octane does make gas harder to ignite, so it is possible I guess that too high octane could make it run poorly but it seems unlikely (it'd be common to have problems running too low octane). did you put leaded gas in?

We donīt have leaded fuel in Europe. Its all unleaded but if you need leaded fuel you need additives.

[Drisump]

Originally Posted by schumicat

octane is measured differently in Europe. 98 in Europe is something like 93 in US. Higher octane does make gas harder to ignite, so it is possible I guess that too high octane could make it run poorly but it seems unlikely (it'd be common to have problems running too low octane). did you put leaded gas in?

You learn something new every day!

[bezza911]

OK, finally got back to the car after a day at sea, it had no issues at all when I started her just then and went for a blast. There was a rain last night, wondering if a little water got into the engine cover and put some moisture into a bank of plugs or distributor possibly. I also wanted to ask, after my 1400km trip from Germany to France, inclusive of my oil leak, as minor as it is, the dip stick range finders (high and low markings) seem to be exactly a litre of oil once the car is warmed up, is this correct? What is the average oil consumption on a 911 3.2 from 85 on a journey like that? I just put half litre in all is as it should be, but I did park on a hill yesterday and heard a nasty rattle in the bows of the engine. I killed the engine and rolled to flat ground, all was fine after that.

Next question, a click in the rear left wheel when turning sharp right, and a noticeable although subtle vibration in the steering also, CV joints?

Thanks as always,

Bez

[dshepp806]

Does she have the stock chip?

Doyle

[Drisump]

From what I understand, there is about 1.75 L. between hi and low on the dipstick and the "sweet spot" is somewhere in the middle when warm. I find that heat (hi ambient temperature) and hard driving will increase consumption somewhat. I recently returned from a trip through Death Valley, where it was +40c..... and the road ranged between -20m and 1600m, my car used a notable (it usually goes 5000km without needing to add) amount of oil for that particular leg of the journey. Cheers

[brd]

Hi bezza911,
I'm running 98 only in a 3.0L engined 911T... perfecto.
And if you're around the yachts, maybe I'm close by too... am not so far from Antibes. If so, you in any club around here? I was considering joining one... but am not interested in any pomp n blah... just driving fun and chillin.

Brian.

[bezza911]

I am down here for the summer based out of Antibes. I lived here permanently until a few years back, but in those days I had a Lancia Monte Carlo Road/Race machine, so not sure of any local car clubs in the hood. Actually, do you know of a good mechanic down here????

I will PM you a little later when this charter ends on the 2nd July and maybe we can meet for blast up to Gourdon/Castelaine way. Used to take my ducati up there every Sunday, some great food as well

[brd]

Ah... sounds good ... and another Ducati rider too! :-)
There is Caruso... but known to over charge on the hours. I got to know a guy in Nice - AAPS - Very tidy work and reasonable, not particularly Porsche, but tasty classics there from time to time. Am considering asking to overhaul my 915 box.
http://www.garage-aaps.com/index.htm

Brian.

[tcar]

Originally Posted by twistoffat

We donīt have leaded fuel in Europe. Its all unleaded but if you need leaded fuel you need additives.

We don't have leaded fuel here, either.

[M.D. Holloway]

I would think you have contaminated fuel - perhaps water?