I think this should do it?
So now I need to think about fuel additives. First off I suppose they are unlikely to do any harm (although I believe I read recently of one that had been withdrawn because it was "eating seals" - which in a modern direct injection petrol or diesel engine could cost mega-bucks to sort out?) Most of the credible independent test reports I've read seem to say that, in most cases and at best, the benefits are negligible? Applying the little "grey cells" to this I think there are 3 main areas where you would hope to see benefit. Better fuel economy and, possibly, an increase in performance. Keeping the system, including the inlet tract and cylinders themselves, clean. Providing increased lubrication to the highly stressed parts of fuel injection systems. Particularly relevant now we have these direct injection petrol systems running unbelievably humongous pressures (petrol, unlike diesel, has no inherent lubricating properties,)
Maybe the first, and most obvious answer is, instead of spending the money on an additive just buy the best fuel! In this regard, although I've never bought it, I have read so many recommendations for Shell V Power that I think that's the one I would go for. There's also another consideration. Pretty much all engines sold here (UK) have to be able to run on basic 95 RON fuel (RON being Research Octane Number which quantifies the fuels ability to resist Knock - pre ignition) Most modern engines (especially the latest generation of turboed offerings) incorporate "Knock sensors" and an engine so equipped will advance it's ignition firing point until it detects "Knock" If you run such an engine on a higher octane fuel like V power or Momentum you are likely to get more performance and, maybe, slightly better fuel consumption as the engine's ECU can make better use of the higher octane (maybe 98 or 99 RON) fuel. An older engine, or any engine, without a knock sensor will not be able to adapt it's ignition timing to take advantage of the higher octane fuel so no advantage will be seen, although the superior additive package in the more expensive fuel may be advantageous to the long life of the engine. We run all the family vehicles - 6 at this time -on supermarket fuels and have done so for years. We keep our cars 'till they become "beyond economic repair" and often exceed 100,000 miles before buying a replacement. However I would like to try the V power in the
Ibiza, just to see what it's like, but it's just too convenient to nip round the corner to Morrisons!
So, finally, we come to those magic wee bottles of fuel additive which promise so much. I have to say I just don't know! I think some of the ones that claim to clean things out do seem to have some effect and some are probably better than others - Cataclean and Forte are two that come to mind. But, especially on diesels where inlet carbon fouling is a big issue, their effects are not as good as a manual De-gunging! I cleaned the seized turbo variable vanes on my boy's 1.9 PD Fabia (which had caused it to go into "Limp") by dropping the exhaust and squirting oven cleaner into it. Applied the cleaner 3 times cleaning out with the garden hose each time and it worked just great for at least the next 3 years 'till we sold it! I got very worried about diesel pump and injector needle wear when they lowered the sulphur content in the fuel a few years ago and, after a lot of research, started using Wynns Eco Diesel in my 1.9VE tdi Cordoba Vario. This is an additive you add to each tank of fuel and claims to do many things including increase lubricity of the fuel. I stripped the injectors out at around 100,000 miles and took them for overhaul to my local diesel specialist. He charged me £25! that included 4 new sealing washers! He said there was nothing to do, just tighten up the blow off springs a little to compensate for age! Was that due to the Wynns? who knows? I'm now running Archoil AR6900-P MAX (bought from the "Powerenhancer" people - very helpful people) in the
Ibiza because its a direct injection petrol so liable to inlet tract carbon fouling. This product claims to specifically address this
problem, I haven't yet found another, whilst also increasing the fuel's ability to lubricate components in the fuel system. Who knows if it will work. I plan to strip the inlet manifold off at around 30,000 miles for a look - which will be interesting with it's integral water cooled heat exchanger but she'll be needing a coolant change by then anyway so why not? Have a Google at the "Oilem" site for some very interesting stuff on this and other subjects.
Crikey! I think this has turned into the longest post I've ever seen! Hope it hasn't timed out and all my efforts disappeared into the ether! I hope some will find this useful and I'd love to hear opinions from others - Additives have always fascinated me - They seem to promise so much don't they?
Regards and stay safe everyone
Jock