Occasionally my 1996 Discovery turns on, but won't stay on. The starter works normally, the plugs are firing, but unless I press on the gas pedal to keep the RPM high the car shuts off. After almost a minute of reving the engine high, the car stays on and I can drive. I was suspect of the timing chain and had it replaced, but the problem continues. I've used fuel injection cleaners, but the problem continues. I've changed the plugs and wires and still the problem continues. This problem happens whether the car is hot or cold.

Any ideas would be much appreciated.

Thanks....