Vehicle & Technical > Range Rover

RR Classic Starting problems

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FITZ4X4:
Most likly culprit and cheapest to replace is the Coolant Temperature sensor. Thses are prone to failure, they are easy to change and cost about £10.

If that fails to cure the problem it could be the Extra Air Valve or it's switch, the Thermotime Switch. These are the EFI's equivalent of a choke.

Heres some info you may find useful.

Extra Air Valve
The EAV allows extra air to bypass the throttle butterfly. This increase the engine RPM on idle when the engine is cold and prevents the engine stalling. When the fuel pump is running current is passed through a heating coil in the EAV. This heats a bi-metal leaf spring that slow closes the vavle until the engine is warm. Once the valve closes the heat in the now warm engine prevents the valve from opening until the engine stops and cools. On old engines this valve often sticks due to oil residues. It can often be clean sucessfully using carb cleaner.

Thermotime Switch
The thermo time switch controls the operation of the cold start injector. It is basically a pair of contact points, one of which is mounted on a bi-metal strip. A heater coil is fitted around the strip. The system works when the ignition switch is in the "crank" position. Whenever the bi-metal is cold the points are closed and the injector is operated. During the time the contacts are closed the current is heating up the strip. After max.12 secs (depending on ambient temperature) the bi-metal opens the points and injection stops. When the engine is already hot the bi-metal strip prevents the injector to operate during cranking. Notice that the extra air valve uses the same basic principle of a heated bi-metal strip.

Coolant Temperature Sensor
The Coolant Temperature sensor is located at the front of the inlet manifold in the coolant gallery.It can be mistaken for the thermotime switch as they are mounted side by side but the coolant tempreture sensor is less bulkier. It gives a signal to the ECU for engine temperature so that the ECU can inject more or less fuel depending on engine temperature. It does not affect the cold start injector!

Agility eye:
Thanks FITZ4X4 some good information their i will have a look at them.

Range Rover Blues:
Check your coil too, had that happen recently myself.

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