Another bit of anecdotal is that anything other than vmax or ultimate diesel (i.e. more additives) causes my 'tuned' VAG diesel to go into limp mode when it hits full boost, almost without fail. The additives do appear to be doing something....
In general they thought that you get extra engine life and more mpg with a branded fuel. We were talking about modern cars though.
electronics are the new rust. The costs of trying to trace an electronic fault can be massive, and unpredictable. A simple electronic failure (like the ABS light coming on) can render a perfectly good car an economic write off, and electronic circuitry is becoming less, rather than more reliable as QC drops. I was chatting to an RAC man about 3 years back, he said ECU failure used to be well down their list of possible causes of breakdowns, now it is near the top. The circuit boards and electronics are just not the same quality as they used to be, and there's a lot more of them!!
Also, like many industries, quality has dropped dramatically because people keep demanding lower and lower prices, or so manufacturers think. People don't think about things like the residual value of a good quality, reliable vehicle being important or worth paying a bit extra for, everything is dumbed down to the lowest price.
I bought a few 1/2 litre plastic bottles, cheap on eBay, http://www.ebay.co.uk/itm/NEW-5-x-5...Equipment_Lab_Supplies_ET&hash=item338ac75c74 and a 25 litre container, http://www.ebay.co.uk/itm/OUTBOARD-...at_Engines_EngineParts_SM&hash=item5198f0271e not so cheap, and decanted.
My diesel golf died with 20,000 miles on the clock at 3 years old. Main dealer said the fuel pump was worn out but their computer could not tell them that! I'll never buy a modern diesel again.
it doesn't put me off buying a new car, I have a 2012 hilux from new and my IQ3 from 4000miles, but it would definately put me off, say, buying a 10 year heavilly electronic car.For what it's worth I would be hesitant to write off ever giving the new stuff a go based on a bad experience. Again the caveat is that this is just my experience and is not generalisable to all modern equivalents but it does give an opposing experience.
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