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Hi Philip,

The short answer is that there are some benefits to using additives, but they’re not a miracle cure. Some additives, such as Redex, STP, or Dipetane, can apparently help to reduce the build-up of carbonised particles of soot and burned fuel on the insides of your engine, which can lead to improvements in reliability, fuel economy and emissions.

That said, there’s little here that’s scientifically proven. The benefits of additives tend to be more word-of-mouth than provable fact, but there’s certainly no harm in using them and if you notice a benefit, well that’s all to the good.

I would suggest that you’re better off sticking to a strict service regimen, using original parts and a qualified technical, than relying on additives though. And of course, as you already know, diesels need to be driven regularly to stay in good condition.

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Hi Steve,

Generally speaking, no you shouldn’t avoid, but of course it’s not that simple. You’re quite right, Volkswagen does claim, and presumably would claim, that its updates do nothing to alter engine performance. There is some back up to this claim, though, as the fixes had to be approved and signed off on by the German federal transport authority, which at least gives some independent oversight to the process.

Now, there have been some reports in the press about issues with the updates, such as higher CO₂ emissions and a degradation in fuel economy, but those are as yet unverified. I think, in general, you should be fine buying a Volkswagen car that has to be recalled, though, if it turns out there are any issues, they will simply have to be brought back in again and fixed, but fixed better this time.

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Hi Meabh,

No, don’t send off the V5 — you’ll need that and Revenue in Ireland will send it off to the DVLA in Swansea when they’re done with it. You’ll also need proof of sale or a receipt, proof of date of the car’s entry into the state, a VRT declaration form that you can download from the Revenue website, proof of your own address (house bills etc), proof of your PPSN number and documentation confirming the vehicle’s CO₂ emissions — the V5 should cover that nicely.

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Hi James,

Assuming that it's the supercharged V6 S, with CO₂ emissions of 213g/km, it'll cost €1,200 a year to tax. 

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Hi John,

For that model year the XF had CO₂ emissions of 149g/km so tax of €390.  

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Hi Mark,

For the new model G30 5 Series, the CO₂ emissions for the 520d SE are 108g/km, so that means annual motor tax of €190.

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Hi Declan,

If it is, you’ll get a letter from Volkswagen to ask you to book the car in for an inspection. If you’re still concerned, contact your local dealer to check.

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Hi Hugh,

Assuming you mean the Volkswagen diesel software update, no, it shouldn't. Volkswagen has had to clear all the updates with the German federal transport agency to comply with a ruling that any changes won't affect the CO₂ emissions or fuel economy of the cars. 

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Hi Seamus,

By any chance is yours the automatic version, with the larger 18-inch wheels? We tested the manual gearbox version that did indeed at the time have a CO₂ emissions rating of 147g/km, whereas the automatic model, with four-wheel drive, was rated at above 180g/km. 

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Hi Ignacio,

There are two hybrids that are far cheaper than anything else, but we have to mention both as they’re slightly different in the way their hybrid systems work. The cheapest full hybrid is the Toyota Yaris Hybrid, which starts at €19,250 and which has impressively low CO₂ emissions of just 75g/km.

Toyota has also recently updated the Yaris Hybrid so that it’s much nicer to drive than it used to be. The other is the slightly cheaper Suzuki Baleno 1.2 DualJet, which isn’t a full hybrid like the Yaris, but a mild hybrid that uses a smaller battery and clever starter/generator to take strain off the engine to help save fuel. That emits 94g/km and costs from €18,995.