Great Wall X200 Pricing and Specs

It all depends on the model and variant of the vehicle you’re talking about, but, generally speaking, the fuel rail pressure sensor on a turbo-diesel engine will be somewhere along the fuel rail. But, even if you know for absolutely certain that this sensor is the problem, we have to advise against any amateur mechanic taking on this, or any other, job that deals with the fuel system. That’s because the fuel systems on a common-rail turbo-diesel run at incredibly high pressures. So they’re dangerous things to fiddle with.

In some cases, the pressure could be enough to slice fingers off. Which means you have to know the exact process to follow in order to bleed off any residual pressure in the fuel system (even if the engine hasn’t run for days) before you can safely tackle jobs like this one. Leave it to the experts, in other words. Also, a specialist is a chance to be able to make a more accurate diagnosis than the one given by an online forum of dubious credibility.

When a whole bunch of electrical and convenience items go on the blink all at once, the prime suspect is the vehicle’s body computer. This computer controls all the functions you’ve mentioned as well as plenty more including the entertainment and climate-control systems, the powered seats (if fitted) and even things like the seatbelt warning lights and buzzers.

An auto electrician is your best bet at this point, and chances are they’ll have seen this exact problem on similar models. Ultimately, you’ll probably need to replace the body computer, but you can try this trick first. Disconnect the car’s battery and leave it disconnected overnight. Next morning, hook it back up and see if the various functions have returned. Disconnecting the battery will sometimes force a reset to the factory settings and will return the body computer to normal service. It’s not a guarantee, but definitely worth a shot since it costs nothing to do.

Like a lot of relatively modern vehicles, the X200 doesn't use a throttle cable, but is instead what's known as throttle-by-wire. That means that the accelerator pedal tells the car's computer what position the driver has placed it in, then the computer tells the throttle to respond accordingly.

It all works on electronics and position sensors and if anything goes wrong with that arrangement, you can get erroneous messages being sent to the throttle with the symptoms you've mentioned. An electronic scan of the vehicle should reveal what's wrong as the computer will have recorded fault codes with any of this electronic gear.

Beyond that, it could also be something rather more mechanical such as a sticky stepper motor (that physically opens the throttle) or even a vacuum leak. It could even be a fault with the electronic protocols that tell the engine to increase its idle speed when, for instance, the air-conditioning it turned on. Again, though, a scan at a workshop should reveal all.