Honest John: has Porsche garage given me the slip over oil problem? 

Our consumer champion on the best course of action if your car's engine oil has been overfilled, with potentially catastrophic consequences

Porsche Boxster - cutaway view
The original Boxster's mid-mounted flat-six engine is more susceptible than most to overfilling with lubricant

If your car has developed a fault, or for consumer advice, turn to Honest John by emailing [email protected]

Over and out?

Due to dissatisfaction with my Porsche dealer, I took my 27,000-mile, 2014 Boxster 2.7 for a major service at an independent with a good reputation. As I drove home I had a warning after 15 minutes saying that the oil level was too high but it was safe to drive. The garage said it was nothing to worry about: I should return the car at my convenience and they would drain the excess. Since the oil pressure was normal, I was satisfied with this advice. The next day I started the engine and it ran roughly and emitted substantial blue smoke, indicating that a significant amount of oil had entered the combustion chambers. The garage agreed to sort the problem. Although there may be no damage, it is possible that other things may be affected and carbon build-up on the pistons could lead to pre-ignition. While I appreciate that the Boxster oil level is difficult to get right, it is clear that the overfill was not slight but substantial. What should I demand of the garage? IN

This is a flat-six engine, so the oil will have entered the combustion chambers via the valves. You are correct about the potential damage this could have caused. So, to prepare for this, send a letter to the principal of the specialist garage that carried out the service and oil change listing the likely consequential damage and holding him liable. Send it by Royal Mail Special Delivery, keep a copy and the certificate of posting, use the reference code to check it was delivered and print out the certificate of delivery, then staple them all together in case you need them in the future, to prove you attempted to resolve the matter reasonably without going to law.  

Mains chance

My daughter is paying £525pm for a four-year personal contract plan (PCP) finance deal on a Range Rover Evoque. The Land Rover warranty is about to expire and they are offering extended cover – £850 for 12 months, which includes breakdown assistance. Is there a cheaper, better value alternative? If she is able to escape from her present PCP contract, what suggestions do you have for a hybrid replacement? MC

I would check www.motoreasy.com for competitive quotations, taking care to read through exactly what is covered and what is not. If she can get out of the PCP on the Evoque, I suggest a switch to a self-charging or plug-in hybrid electric vehicle. JLR has announced Plug-In Hybrid Electric Vehicle (PHEV) versions of both the Evoque and the Land Rover Discovery Sport. The Kia Niro, eNiro and Niro PHEV, Toyota C-HR 2.0, Lexus UX, Honda CR-V hybrid and Toyota RAV-4 hybrid are among the SUVs I favour, all of them being self-charging hybrids. Coming soon are a Plug-in Peugeot 3008 Hybrid4, Citroën C5 Aircross Hybrid 4, Vauxhall Grandland Hybrid 4 and Ford Kuga. Audi does a 48v hybrid version of its Q3 Sportback. And the Suzuki Vitara is now available as a 48v self-charging mild hybrid.

Dear is the key

The Honda Jazz has reputation for practicality and reliability, but why does GR's keyfob battery have such a short lifespan?

My wife and I share your high opinion of the Honda Jazz and have run one from new in November 2016.  However, we now have a worsening problem concerning the duration of key battery life. From new, these lasted for more than two years before replacement was needed. Since then, however, the batteries rarely last for more than two months. With replacements from Honda costing £3 to £5 per battery, it's becoming an expensive alternative to an old-fashioned key. Have you any idea what might be causing this? GR

Investigation determined there are three sizes of remote keyfob battery: DL4250, CR2032 and CR1632. You might be using the wrong size. I suggest you take the keys to a branch of Timpsons (found in many supermarket foyers and car parks). First check that you have been using the correct battery. If you have, then ask Timpsons to copy one of the keys and its code into a new key. See how the battery lasts in that. If it's fine, then have the other key copied and coded into a replacement. Something might have happened that causes the original keys to stay live and decreases their battery life.

Loud pedal

Quiet life: AM wants some tyres that develop less road noise than his existing Continentals

I have a 2016 Volkswagen CC 2.0 TDI with Continental 235/40 R18 tyres that need replacing. From a comfort point of view they are acceptable, although the noise on certain roads is very intrusive. What make and type would be more suitable? AM

The reason for the noise is the low profile of the 235/40 R18 tyres that have now worn to the extent that more of the tread is in permanent contact with the road. Replacing them will have an immediate effect. To reduce the noise permanently, you could fit 17-inch wheels with 205/50 R17 tyres. I'd go for Michelin Primacy 3 or Primacy 4, or Continental Premium Contact 6. Or, for all-weather use, Michelin Cross Climate or Continental AllSeason Contact. You will need to swap over the tyre valve TPMS monitors and also disclose the change of wheel size to your insurer. www.tyremen.co.uk can supply the new wheels and tyres. Sell the old ones on eBay.

Going straight

How do you get a wayward Porsche Macan to track straight and true? 

I was disturbed to find the plies exposed on the outside shoulder of one front tyre of my new Porsche Macan, despite there still being 4mm of tread left. I took it to the supplying dealer for alignment and told them it should be done under guarantee. They refused, saying they had no way of knowing “what I had hit” and tried to charge me £400. I settled reluctantly for £320 but, after that, the second set of tyres wore in exactly the same way at the same mileage. Also, the car was unstable in a straight line on bumpy roads and had a tendency to drift left from new. On recommendation from the Porsche Club I took it to Centre Gravity at Tamworth, who found every wheel out of spec in every possible way: camber, toe-in and caster on the front. It took them six hours to get it right and the car is transformed: straight as an arrow and pin-sharp steering. I wonder how many other cars are incorrectly aligned. What do you think? JF

I would put in a Moneyclaim to the Porsche dealer who charged you £320: www.gov.uk/make-money-claim. Most cars come off the end of the production line very haphazardly aligned. One exception is Mitsubishi, whose 4x4 pick-ups are aligned properly at every articulation of their axles with the result that a set of tyres can last 50,000 miles. Shame on Porsche or its dealer for not aligning your car properly, although the car might also have suffered transporter damage on its way to the dealership.

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