If your car has developed a fault, turn to Honest John by emailing email@example.com
My car has been written off by a third-party collision while parked outside my house. Am I correct in understanding that my insurance should reinstate me financially to where I was immediately before the collision? DR
The driver who crashed into your car is liable to restore you to the position you were in before they did the damage. Their insurer usually interprets this as giving you market value for your car before it was wrecked and county courts have upheld this as a "reasonable" settlement.
Obscured by clouds
With the decline of diesel and ultimately petrol cars, plus the introduction of hybrids and electric cars, are there any manufacturers that use solar roof panels to recharge batteries? TM
A solar roof panel is an option on the Toyota Prius PHEV. But in the UK the annual sunlight is only enough to power it for about 412 miles. It does better in Rome, where annual sunshine takes it 720 miles.
Firmly in favour
After 20 years of driving BMWs I decided to change and now have an Audi S5, which comes with normal tyres and a space-saver spare. I’m thinking of switching to run-flat tyres because I don’t intend changing wheels on the hard shoulder. What’s your view? GP
Eminently sensible. The car will already have a tyre pressure monitoring system, so no problem, but for the same tyre size the ride will be a bit harder.
Money for nothing?
My grandson has a Vauxhall Astra diesel van with a broken cambelt. Can we anticipate restoration or replacement? WW
If valves have hit pistons the engine is probably scrap. It might be a matter of sourcing an engine and having it rebuilt by a member of www.fer.co.uk, but this could cost more than the repaired van will be worth.
Relay saying something
I have a 2011 Peugeot 308 1.4 petrol that worked perfectly for 18,000 miles, but then stalled while I backed out of my drive. Green Flag arrived and found that the petrol pump fuse had blown. They tried two more fuses, which also blew. They towed the car to my local garage and two more fuses blew. An ECU fault was suspected, but no fault shows up in diagnoses and fuses keep blowing. Any ideas? KT
The fuel tank lifter pump is earthed. And the power supply to it comes through a relay that is also earthed. If the pump is working, then by process of elimination, the culprit must be the relay.
Making the cut
I have a 1999 VW Golf GTI with 89,000 miles on the clock, pretty much all short journeys. Two owners, new tyres, new battery. I just want to hang on to it as it’s cheap to service and bombproof. My garage thinks the same. But if something expensive goes wrong, what’s similarly bombproof and cheap? SS
Reader feedback (and my own experience in the 1980s) tells me that VW Golf GTIs are far from bombproof, so I think you have been lucky. Generally (with some exceptions), Hondas and Toyotas seem to be hold together better.
Decline and fall
I have taken my 12,000-mile, 2015 Jaguar XE back to the dealer for numerous software updates. Each time it seems to affect the stop/start system. They claim that the updates take so much power from the battery that this feature will not operate. What is likely to be wrong? I am stuck in a four-year PCP contract. GW
That is not much of a mileage so it is likely that the car's battery has lost its capacity to hold a full charge of 14 volts and that is why the stop/start is not working. Once a battery's capacity has declined it cannot be recovered, so the car probably needs a new battery – and stop/start batteries are expensive, usually £200-£300.
Failing, the pressure?
The oil light has come on in my Honda Civic 1.6 diesel. The level seems OK when checked. It was serviced by Honda only six weeks ago. Any ideas? RB
It might indicate a lack of oil pressure, in which case you’d better get it checked urgently and not drive the car. Get straight on to your Honda dealer. The oil pump might have failed.
To replace front brake pads on my 2013 Ford Kuga 2.0 TDCI I’ve been quoted almost £900. Seems steep to me. DR
Steep? That’s pretty much vertical. I suspect it needs new discs as well as pads, but £900 is still expensive.
I own a 1991 Ford Granada Ghia 2.0 auto that has been garaged and used only lightly during the last 14 years. Could you suggest suitable ways of moving it on to a new home where, hopefully, it will continue to appreciate? GC
I am about to start a job that will involve about 500 miles of motorway driving per week. I want a used petrol car, either a convertible or a fairly economical SUV, for about £15,000. What should I look at? AC
You could get a Fiat 500C TwinAir for £15,000 after a bit of bargaining. It does about 45mpg. You might get a used Suzuki Vitara S 1.4T Boosterjet for £15,000. Or a used Peugeot 2008 1.2 Puretech 130. Both of these also do about 45mpg. For more fun and better economy go for a Suzuki Swift 1.0T Boosterjet mild hybrid, which can return 55mpg.
State of shock
I need to replace broken rear springs on my Vauxhall Astra estate (MoT fail). Halfords "recommended" replacing the dampers as well, which seems excessive to me and unnecessarily expensive. The car has done 35,000 miles and does only about 3,000 miles a year. What do you reckon? RH
If the springs have broken then the dampers are probably in a state of shock, too, especially on an estate that carries loads. If you don't replace them now you will probably have to replace them within the next year, then pay for the dismantling and refitting all over again.
Right way around
You recently cast a slight aspersion on JLR’s Ingenium diesel engine. I have had, from new in September 2015, a Jaguar XE diesel 180. The engine, and indeed the car, is very responsive. What it is about the engine that seems to put you off? JK
The XE, XF and F-Pace do not have the same problem because the engines are installed longitudinally and the DPF is close-coupled to the integrated exhaust manifold of the cylinder block. There is no room for this in transverse-engined models, so the DPF rarely regenerates passively on engine heat alone.
I am in the market for a small, tall SUV with as many safety features as possible: high driving position, petrol engine and automatic transmission are all on the list. Exhausting trawls around numerous showrooms leave me with models rather larger than required and, in many cases, lower than meet my specification. You seldom if ever mention the Ford EcoSport that seems to provide most of the bells and whistles I would like. Anything against it? BM
I don't mention it because it is a fairly awful vehicle: it doesn't ride or handle well, it has a dry clutch Powershift transmission that’s prone to failure, a turbocharged one-litre engine that’s prone to losing its coolant and the rear door opens the wrong way for the UK. Try a Peugeot 2008 or a Kia Stonic.
Could you clarify the damage caused by having a tread depth discrepancy of more than 3mm across the axle on a BMW 3-series xDrive? AH
A disparity in tread depth is detected by the system as slippage, so the electronics then try to compensate for it and work overtime, leading to wear in the system.
Czech out queue
The time has come to replace my wife's Skoda Roomster, but what else has the same access and load carrying ability in a small car? GE
A Honda Jazz is phenomenally versatile, with a flat load-deck floor. You could also consider a Peugeot 2008 or a Renault Captur.
My son is looking for a small automatic and you recommend torque converter models. Does the six-speed Vauxhall Corsa auto have a traditional torque box? TS
The six-speed auto with the 1.4 engine is a torque converter. Stay away from Easytronic automated manuals, which can be troublesome.
Error and trial
You frequently recommend Shell V-Power diesel in preference to supermarket diesel. It's a lot more expensive, so I have never used it. After 130,000 miles in my Skoda Roomster 1.9 TDi, however, there is some slight engine judder at low speed. If I switch to V-Power, will this give the engine a good clean-out, or have I driven on ordinary fuel for too long? ME
It might be too late, but try a diesel fuel system cleaning additive such as Wynn’s, fill up with superdiesel, then stick to the same brand so you always feed your engine with the same additive package.
Rim with a view
My BMW 320d M Sport has 19-inch wheels with run-flat tyres and I would like a smoother ride with less road noise. Can I fit smaller wheels to this model, as I believe it has larger brakes than standard. LF
The F30 320d ED came on 16-inch wheels with 205/60 R16 tyres that give the best ride - and you can get Michelin Cross Climates in that size. Fit the very smart 320d ED 16-inch wheels or buy a set of 16-inch Alutecs from www.tyremen.co.uk.
TC’s top Cat
We have a 2006 Jaguar XJ6 Sovereign 2.7d, which we love. It is in great condition but – having read your review of the model where you cite corrosion as a problem despite the aluminium body – I have noticed two small rust spots on the bottom of the offside doors. How can we best treat the problem? Also, should I run this car on standard diesel fuel or a more expensive premium brand? TC
You will need to consult a body shop about the electrolytic mixed metal corrosion on the doors. Run the car on one brand of superdiesel and stick with that.
My 1991 Saab Turbo has been extremely reliable and still has most of the original parts intact. Recently the fuel gauge, which is enclosed in a sealed unit on the dash panel, seems to show irregular readings. I am not able to ascertain how much fuel is in the tank. My very good local garage says it could be the sender in the fuel tank, a faulty connection somewhere or a sticking needle. Any thoughts? MS
You have received good advice. It’s most likely to be the float sender in the tank, but could be the earth to it or else the gauge needle. Best to check earth first, then the float sender. I’d try to avoid dismantling the dash unless it is unavoidable.
Someone dumped a car without permission on a private car park in our village. The culprit has been asked a few times to remove the car, but still hasn’t after a year. What can we do next? Report it as illegal fly-tipping? The police say they can't do much. HT
The police won't do anything unless the car is illegally driven. However, the owner of the car park can apply to the DVLA for the keeper’s details citing the “just cause” that he wants to resurface the area and the car is in the way: www.gov.uk/request-information-from-dvla. Once that is done they can send a letter to the keeper by Post Office Special Delivery, informing them that if the car is not removed within 14 days, it will be taken to a place of storage where the fee will be whatever per day.
I know that you have addressed the potential problems connected with VW Group DSG transmissions over several years or more. Is my DRS-equipped Skoda Octavia vRS likely to be bothersome? DD
That has the six-speed DQ250 wet clutch DSG, which is one of the better ones but needs fresh fluid and filter every 38,000 miles.
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