Red spark plugs = poo Tesco fuel!

[james944]

Changed my spark plugs after 12 month and 3 out of the 4 were literally scarlet red.

Looked up on a few pages as to why and it seems Tesco (who I used prodominately for 98 fuel) have a bad rep for fuel quality.

Anyone else had this?

Also cylinder 4 plug was coated in a crusty black something!

 

[924nutter]

See your Haynes manual, a crusty black stuff is carbon, usually, so oil is probably getting in to that cylinder; however bad you allege Tesco fuel to be I doubt that the ecu is clever enough to send all the bad fuel to one cylinder. Completely mystified by the red colouration unless their tankers also tranport red diesel and some of the maker dye is getting in to the petrol.

 

[Copperman05]

I doubt this is fuel related, tesco 99 is pretty good stuff in my book.


Edd

 

[Hilux]

Check the plugs are the right temperature rating? They`ve been running real (very) hot in my view.

Get your injectors cleaned/checked.

Check your fuel rail pressure.

Check your pre-pump filter.

 

[tobybanks]

What colour is your antifreeze? It was one of the symptoms of a leaking HG on mine, even though there didn't appear to be much coolant loss.

 

[JamesO]

Is it not just the additives in the fuel that gives the plugs the red colour? When I only used v power in my lux the plugs had a red tinge to them.

 

[ja944cab]

I've used my car too infrequently recently to know how it likes tesco yet but my brother runs a 600hp skyline and he says tesco 99 and vpower are the only supers he doesn't have to add octane booster to. So they're my fuel of choice for now, they definitely worked well the last couple of days

 

[David.H]

I have always run my 944S" Cab on 95 Octane (cheapskate!) that's what it says on the flap!
What advantage to 99 or vpower?
DGH

 

[ChasR]

On a stock car the difference is debatable.

On a tuned car (turbo espeically), the higher octane fuels can be an effective safeguard against knock/pinking. I know that on modern cars with adaptive knock sensors, many people notice a difference with V-Power. Christ, even on my PD engined Passat it ran miles better on V-Power Derv over the normal stuff when compared to previous diesels (common rail or old school). I put that down to PDs allegedly not liking biodiesel (VW themselves say that if they are run on Biodiesel for quite some time, the fuel filter changes have to be shortened dramatically (read, short than the oil changes (not the Longlife type).

 

[GlennS]

I avoid putting Tesco 99 in the 944 although I do run it on generic "Super Unleaded" exclusively.

Tesco Momentum 99 achieves its "octane boost" in large part from the addition of 3% Methanol (http://www.tescopfs.com/momentum99/specifications). This is in addition to the 5% Ethanol permitted under BS EN 7800 giving a total "alcohol content" of around 8%.

Porsche issued a statement in 2011 with regard to E10 fuel (http://www.porsche.com/uk/accessori...ws/classicnews/?pool=uk&id=2011-05-23-classic) to the effect that their engines prior to 1996 are compatible with up to 5% ethanol but not 10% ethanol.

The "undesirable" side effects of methanol on an engine are very similar to that of ethanol (http://www.methanol.org/energy/transportation-fuel.aspx) therefore I consider that 8% total alcohol content is pushing the limits a little further than I am comfortable with.