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Discussion Starter · #1 ·
Just trying to gauge people views here.

What fuel do you run your Golf on. Of particular interest are V5 owners. 95/98/99 RON?

I have a 2001 V5 170 that has been running a bit rubbish recently, and a friend of mine has done a test on VAG.com and told me that it is running 132bhp and suffering from big ignition retard on some of the cylinders, as well as bringing up a knock sensor fault.

What I dont know is what the previous owners ran it on, but I am presuming that a change to better grade fuel would be more beneficial for the cars running? I currently use 95, but it may be used to 98? The car was serviced 4 months ago, but has been slowly losing its performance (not a lot but a liitle) and the last few weeks I have been experiencing warning lights and VAG.com fault logs. MPG has also fallen noticably since I got it!

The handbook states that 95 RON is perfectly fine, but it seems to be suffering as a result over the long term? Would people strictly recommend 98 or higher for a V5?

Has anyone got experiences or feedback having ran their car on both normal and super?

Along with a full service next week, I am hoping to get back those 38 lost horses!
 

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I think with most petrol Golf's of that period they were recommended to run of super plus (98 ron) fuel. Even my 1.6 Bora runs poor on 95 ron (bad pinking and sluggish pulling) compared to the Optimax which I now use all the time.
 

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i use Optimax 98 Ron in mine ....... anything less than that and it dont like it

But with regards to V5 Models and there petrol .......I Belive j4ohnw on here uses normal 95 ron
 

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Discussion Starter · #4 ·
The handbook doesnt stipulate that it MUST run on 98 like some performance engines, and I wouldnt class the V5 as a performance engine as such, but it seems to be gradually running worse and worse on 95, and now I am having these problems with knock sensor faults and warning lights. Thats said, since I have had the faults cleared it has had no warning lights or misfiring problems, but I am driving it gingerly to use the rest of the fuel in the car before i convert to 98/99.

I am presuming that two or three tanks of 98 will enable the sensors and ECUs to re adjust to the better grade of fuel and make it run alot better.

It may well have been used to 98 or 99 by its former owner?
 

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they do seem to like better grade fuel

i had to call vw assist out once due to me putting in low grade fuel .....was on a trip to cornwall 300 odd miles and just as i got there the ligth came on , so looked for the closest garage and not thinking just put it in , it run like a pig after that until i got the sensors rest

so optimax is the only stuff that goes in now

just a sugestion .....how much fuel ya go in ya tank , might be worth topping it right up and adding some miller octane booster in that should bring the levels about right as if ya just have 98 in

yer i would say 2 - 3 tanks and then it should settle down and the ecu should learn what ya have in it
 

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I've done 40k in my 01'170 (she's on 70koverall) and pretty much use BP Ultimate all the time (no shell stations around where I live) and occassionally use Tescos 99ron Superunleaded, being cheaper and faster...

I'd have to say that the Tescos stuff gives my car noticeable zip above other fuels, though I also like to believe that I am doing a little less damage to the environment (in my big 2.3litre V5 with average 28mpg!) and doing some good to my engine (with all the detergents, etc) in using Ultimate. - So I fluctuate between the 2 and don't have any problems with either 99-98ron.

Occassionally (in emergencies - or skint - or going on a boring 200mile motorway journey) I'll put a tank full of 95 ron in - the car will feel less responsive, sluggish. But I don't get any warning lights, etc.

Personally I wouldn't put any additives into the petrol tank.

s
 

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The handbook doesnt stipulate that it MUST run on 98 like some performance engines, and I wouldnt class the V5 as a performance engine as such, but it seems to be gradually running worse and worse on 95, and now I am having these problems with knock sensor faults and warning lights. Thats said, since I have had the faults cleared it has had no warning lights or misfiring problems, but I am driving it gingerly to use the rest of the fuel in the car before i convert to 98/99.
Have a look at the sticker on the inside of your fuel filler cap. That will tell you the grade that should be used.

I would be really surprised if it doesn't say 98. A 1.6 is hardly a performance engine either [:D]
 

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Discussion Starter · #8 ·
It says 98/95 on the inside of the filler flap, which I take as 98 preferable but will take 95 OK (as it isn't 95/98 if you see what I mean)

I always use good quality 95 anyway, usually Shell, and make a point of avoiding supermarket stuff, as round my way there is very little in it anyway pricewise. I have only used supermarket petrol stations a few times since I've had the car, and only because I've had to.

And I usually run full to empty ie full tank at a time.

Alternating between Optimax and Tesco 99 sounds like a good idea to me. Best of both worlds.

Hopefully the car will be back to full health with a full service and a few tanks of 98/99.

Cheers all for your help.
 

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I cant beleive nobody has said this yet but check your MAF as well as your engine may be thinking it is not getting enough air. it is simple enough to do just give it a clean.

What sort of mileage have you done if you dont mind me asking ?
 

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Discussion Starter · #10 ·
No not at all. Car has just rolled over to 82k. Was on 77.7k when I got it. It has a full VW service history, and also had an oil and filter done when I bought it.

Don't know if you have noticed another post I have going, but as a result of the traction control and EPC lights coming on a few days ago, and it developing a misfire and wouldn't idle properly, I had a mate with VAG.com run a test on it, and it came up with brake light switch, knock sensor and air mass meter. Since clearing the memory it has been perfect, but still a bit sluggish compared to how it was.

All the above faults were intermittent. Do the V5's suffer from air mass meters like the 1.8T's then?

And to what extent would that affect performance/MPG/running of the car if it was that that was on its way out?
 

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It can make the car hesitent lack power generally across the whole rev range, it will not show up on vag com as a fault, just give it a clean and see if that helps it is a quick job to do and will give pretty immediate effects.

The only other problem I had with similar symtoms was the throttle body which I cleaned and that got rid of the hesitency, allthough not sure if the V5 suffers from the same ?
 

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Discussion Starter · #12 ·
Is it just a matter of spraying some brake cleaner or similar onto the hotwire element inside the housing like the old XE Vauxhall ones?

Also, I seem to get the impression (from the 1.8T guys) that this will be a quick but not long term fix??
 

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My fuel filler cap says 93/95 ron !  but mine is an august 98 agu. a real young'un !  I just run it on normal unleaded never noticed any difference between ultimate/optimax/super/normal whatever !  but then it's not remapped or anything.
 

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Mine says 98/95. Defo runs better and smoother on Optimax so that's all I use now. Hell, I'm gonna try Optimax on my breakfast cereal [Y]
 

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Optimax for me, but i've got a pluspoints card so always use Shell.

As important as using a high quality fuel is to use a station that has
a high turnover of fuel. Fuel degrades with time - Optimax especially
so due to its additives. It also means you don't get crap from the
filling tanks in your fuel from sediment where the fuel sits for long
periods.
 
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