which to use, petrol or diesel

[6pch]

looking through the forum, i noticed theres not a single topic for " fuel system"
so out of sheer boredom, i`v deciced to rectify this. and declare that petrol works best in my car !

[MyQuest]

Really? How did you compare them....?
Tee Hee

Happy New Year all.

Michael

[mike020150]

Ah but which petrol? Are you a 95 octane user or a 98 man? And can you tell the difference? Mike.

[XK8UK]

For what it is worth I have tried both, can tell no difference, though others swear they can. I'll go a stage further I now only use Tesco's petrol in mine as there was absolutely no difference in performance and quality of running, just cheaper to buy!!

[6pch]

yes i agree, having used both, i can not tell any difference in performance,
but as i know that the higher the octane is, the more better it is for your engine, then i cant help using it every now and then!

but as far as using tescos/asdas petrol, i just can`t do it !
maybe theres no difference, and its from the same plant, but its a bit like buying "own-brand" labels- just seems cheap and naff for a jaguar !

[Nik]

Hi XK8 UK ,
I beg to differ , if you use the current batch of Tesco fuel from down south you might get less performance due to the latest additive .............."SILICON" (might be better to use their diesel )

Best Wishes ,

Nik

[XK8UK]

Quite right Nik, however it is not only Tesco's down here that have had the duff fuel delivered, they are the only ones accepting responsibility though, as it was delivered to Asdas, Morissons and Waitrose (which is bannered BP) as well as some other independants. All were supplied from the same Thurrock storage tanks.

[Nik]

Hi XK8 UK ,

Hopefully I'm not effected as I only use Shell V-Power ( previously known as Optimax ) .
Can't say whether there is any difference between Shell and other products but I think I'm doing the right thing by using a top quality high octane fuel ? Anyone got any different views on what or what not to use ?

Best Wishes ,

Nik

[MarkyM]

Old post but I had to reply as there is an alternative.

LPG works best in my car and I get circa 350 miles for a £24 fill-up
prior to conversion I found it only useful to use Super unleaded (V-power or Tesco's) on every 4th tank

Must have been doing something right as averaged 34MPG on a regular 360 mile run and could squeeze 500 miles out of a tank at an average of over 60 MPH.

Regards

Mark

[nicholls-a5119]

Hi All,

I have recently bought a stunning XK8 1998 Convertible. This beauty has only done 3500 miles over an 8 year period. Total miles is 119000.
The area I bought from is on the south coast and the previous owner regularly filled up at ASDA. As I had to do the same when collecting I filled up at the local ASDA as well. I am usually a Shell user. At this time I occasionally have Restricted Performance light up. Is running rough when idling and is not smooth around 55mph. This car has been very well looked after and the fuel filter was changed 2 years ago. I am sure this is a down to the cheap fuel. I have added some Redex. My plan is to burn off 1/2 a tank then refill with Shell V power, then repeat again at 1/2 tank.

I am confident this will cure and I will keep you updated. Very helpful forum thanks.

Alan

[Andy P]

Hi nicholls-a5119.
Thanks for the input,look forward to hearing the result.
Enjoy your car
Take care.
Andy

[mike020150]

3500 miles in eight years? It sounds like an 'Italian tune-up' is called for. Mike.

[nicholls-a5119]

Maybe. But what is an 'Italian' tune up?

[mike020150]

An 'Italian tune-up' consists of some vigorous usage designed to blow out the cobwebs formed during a lack or use or similar pottering about. Initially, 50 miles energetic (and enjoyable) use should do it, followed by regular exercise. It often helps to do something similar just before taking a lightly used car for its MoT. Mike.

[nicholls-a5119]

A little update for you.

After burning off near to half a tank I then topped up with Shell V power. There has been no change. Still running rough with Restricted Performance. In fact, I now have other warnings showing up. They are Stability failure and the ABS light is now on.

I have spoken with my local garage who advise that it is unlikely to be a fuel standard problem. (Although I will use Shell V power when these faults are rectified). So, my XK8 is booked in this week to be analysed and hopefully sorted. I must say that the other faults only started to light after I had checked through all fuses and checked relay connections, All are good and clean. Maybe because I have temporarily disrupted the power supply to that system. The interesting thing I have found is that the battery has a date stamp on the negative terminal of 18/08. Now is this the 18th week of 2008? Or 8th week of 2018? As the tyres were 10 & 11 years old (which I have now changed) I have a sneaky feeling that the battery has not been changed recently and this is a very old battery. I have not known one to last 13 years!
I have heard that these faults can be thrown up when the battery is not healthy.
I will let you know the result of the garage visit.