Content Starts Here

Ask a mechanic - 12/11/07

Car Mechanic - your answers

You can find the answers below to your mechanic questions - click on the next page link to see more answers. To submit your questions click here

STEAM-POWERED VAUXHALL
Q: I have a Vauxhall Astra 1.7 turbodiesel. When I turn on the heater blower it belches out steam, which hardly helps screen demisting. If it's set to cold it's fine, as it is during the first couple of minutes of driving, but after that - steam! Any ideas what the cause could be? Posted by: dawdafish

A: Yes, you either have a punctured heater matrix (radiator) or a split feed or return hose to it. Alternatively, one of the hoses is loose. If it's the first of these possibilities, matrix replacement is unfortunately a nuisance of a job.

RENAULT'S ROUGH IDLE
Q: My 50,000-mile Renault Laguna Mk II has a slightly uneven tickover and sometimes cuts out upon approach to junctions or traffic lights. It has had a full service and a diagnostic test, but no fault has shown up. What to do? Posted by: gazcop

A: The first thing is to check for intake air leaks, most often caused by detached or split vacuum hoses at the inlet manifold and throttle body. Engine valve wear will also give rise to uneven idling, but as your mileage is quite low, and there's also a stalling problem, this is probably an injection system fault.

NO-BLOW SITUATION
Q: Help. I have no air blowing from the fascia vents and I can't hear any fan operating when I switch the heater blower to any setting. What can the problem be? Posted by: tanyaidavies

A: Most likely a blown fuse; maybe a malfunctioning relay. We can't be of any more direct help because you haven't even told us what type of car it is. Check the fuses first, and if you're not a confident electrician, take the car to somebody who is.

IT WASN'T THEIR FAULT
Q: When my wife took her Nissan Micra for an MoT she was told the clutch needed replacing. This was done for £300 at the same Nissan agency. Two or three weeks later the clutch stopped working, and the garage diagnosed a failed clutch cable. That will cost about £150 for replace, but shouldn't they have spotted its imminent failure when they changed the clutch? Posted by: gordonthornett

A: Not really. They were asked to renew the clutch assembly, not the clutch cable, and they had no reason to suspect that the cable, which is not something you automatically renew along with the clutch, was on its way out.

FOCUS ON THE DAILY GRIND
Q: My Ford Focus makes a grinding noise from the front suspension or brake pads. When I push down on the front of the car (bounce it up and down) it makes the same noise. What might it be? Posted by: pabaker72

A: If pushing down the car's nose recreates it, then it's not caused by the brake pads. It sounds as if there may be a problem with the suspension strut, but before doing something about it, check there's nothing loose contacting any part of the front suspension.

FAVOURING THOSE IN THE REAR
Q: I have a 2002 Ford Windstar with dual heater controls that allow independent heat settings to the front and rear cabin. While there's plenty of heat to the back, when I slide the front-cabin control to either hot or cool it makes a sound as if something is trying to flip shut, but can't. The heater only blows cold air out at the front, although there's clearly heat in the system. What's going on? Posted by: volsrescue

A: You have an air direction flap that isn't operating properly, ie it's not connecting the hot air channel to the front-cabin outlet. The flap may be cable or vacuum operated but could be hard to access, so take the car to a repair workshop.

SMOKESCREEN OF CONFUSION
Q: My Rover 414 failed its MoT test because it produces too much smoke from the exhaust. It's also using more fuel than it used to. What should I do? Posted by: darrenkennedy1967

A: We think you're confused. The 414 is a petrol-powered car, and these aren't subjected to a smoke test, which is exclusively for diesels. However, if you mean the car is exceeding emissions limits, then possible reasons for this are an injection system fault, valve leakage or piston/cylinder wear.

TUG O' WAR
Q: I have just replaced the front tyres of my Nissan X-Trail 2.2 dCi with the same Dunlops as originally fitted. Now, with the steering wheel straight ahead, the car pulls to the right. Also, the steering wheel isn't straight anymore. Posted by: james.perkins4

A: There's no obvious reason why a change of tyres would cause this, unless at the same time the tyre fitter checked and adjusted the front wheel alignment. If this was unevenly adjusted side to side, that could cause the pull and the Steering wheel misalignment.

LACKLUSTRE FORD
Q: What does it mean when your car is struggling to go faster than 40mph? It is a 1992 Ford Fiesta and I had it in 5th gear with the pedal to the metal! Posted by: alice_serras

A: Yes, it either means the engine isn't developing sufficient power - for any one of a host of reasons - or that the brakes are binding (sticking on). If the revs are rising when you accelerate, but that doesn't translate as increased acceleration, then the clutch is slipping.

AN ILL WIND
Q: My 1999 BMW's heater just blows cold air on all settings. Everything else is fine though: it runs okay and doesn't overheat. What could be causing this? Posted by: m.king43'

A: There are four possibilities: 1) insufficient coolant or an air-lock in the heater system; 2) a blocked heater radiator; 3) a coolant valve not opening to allow coolant through the heater; 4) air direction flaps not opening to allow heated air through to the cabin.

Did we answer your question? If not submit one now

page: 1 | 2 | 3