Great Wall Reviews

You may be on the right track with your theory that the fuel rail is not holding pressure overnight. But you could also have the same problems with, say, glow-plugs that are not working efficiently (or at all). In that case, the vehicle will be hard to start form cold and could easily display the other symptoms you’re seeing.

Modern turbo-diesels have a pretty complex (and super high-pressure) fuel system, so there’s plenty to go wrong. A check-up at a diesel specialist is probably the best advice. Don’t be tempted to tackle the problem in your driveway, either, as these systems run at sufficient pressure to remove fingers if you get it wrong.

In fact, a diesel engineer once told me that one of the big concerns with these modern diesel engines is making them tamper-proof to protect inquisitive backyard mechanics.

There are a couple of issues here. The first is that your mechanic may not have the correct scanning tool to be able to interrogate the car’s on-board computer to check for fault codes. And without the correct one, you won’t get far down that track. However, it’s worth following that route as it’s the best, most efficient way to find out what’s really going on inside the car.

Ironically, the same scanning tool required will probably also be able to turn the transmission warning light off. But turning the light off is not the solution; you need to know what triggered the warning in the first place and attend to that. Otherwise the light will keep cropping up, regardless of how often you turn it off.

Continuing to drive with a warning light illuminated risks doing more damage to the vehicle in the long run. Something is not right in your car’s driveline and the car knows it. But you’ll need the right mechanic with the right tools to be able to know what the fault is and how to fix it.

Sometimes the DPF (Diesel Particulate Filter) can become so blocked up that it’s impossible for the vehicle’s onboard systems to clean it. If that’s the case, either manual cleaning or a completely new DPF unit might be required.

A diesel specialist should be able to figure this one out. Until then, you’re stuck with limp-home mode as the vehicle should not be operated without a functioning emissions system, of which the DPF is a crucial part.