Dodge SUV Range

Any time you have a dull, thudding or clunking noise inside an engine, it’s best to not drive it any farther and have that noise checked out. You may be right and the problem is an injector, but if it’s a serious mechanical problem inside the crankcase, you may find it suddenly lets go with catastrophic results.

Even if it doesn’t fail completely, you may be doing extra damage to the crankshaft, con-rods and bearings (and more) by continuing to drive the car. The problem could also be with the gudgeon pin(s) which secure the pistons to the con-rods. This is also something a mechanic would investigate.

The fact that the noise comes and goes with engine speed could be related to changes in the oil pressure masking the noise as engine revs rise. Bottom line? Have the car checked by a mechanic who should be able to pinpoint the noise. But be prepared for major expense if the engine has serous internal wear or damage.

You’re probably right in thinking there’s a problem in the fuel system, but simply changing bit and pieces you think might be the cause is a great way to waste money replacing parts that turned out to be perfectly good, leaving you with the same problem. Take the vehicle to a diesel specialist. The cause could be dozens of things from fuel-pump wear, a dirty fuel filter, a clogged intake manifold, blocked lines and worn fuel injectors. And more.

A specialist diesel shop will be able to take the guesswork out of a diagnosis and will almost certainly save you time and money.

A lot of cars have a function whereby the horn will sound when the car is locked if there's a door, bonnet or boot ajar. It's designed to warn the driver that the car may not be fully secure even though it's technically locked.

Sometimes, the little switches that detect whether a door is ajar can become sticky with grit and grime and don't function properly. Locate each switch and give it a quick spray with electrical contact-cleaner and you might find the problem goes away.