Starting Difficulties

[CORNELL]

I have a 99 Alhambra 110 Tdi which has become very difficult (but not impossible) to start.

 

When the ignition is turned on, the glow plug light does not come on, after 5-30 mins it eventually does and the car starts normally. To date it has never cut out once running. If the engine is warm, the glow plug light will usually come on much sooner allowing the engine to start. The engine will always turn over but will not start unless the light has been on.

 

Having read numerous postings I have tried: -

 

Checking the battery terminals

Unplugging the Engine Coolant Temperature Sensor

Relay 109 working and showing an output

Glow Plug Relay working once it receives a signal from ECU

I assume Glow Plugs are ok as the engine starts imediately once the light is on

The fuel injection solenoid can be heard clicking even when the engine won't start

Immobiliser light on drivers door behaving as normal

Brake lights and cruise control are working so I assume brake light switch to be ok

 

Diagnostics have identified: -

Air Mass Meter Sporadic (Code 00553) (There is no loss of power/performance)

Engine Speed Sensor Sporadic (Code 17978)

 

I assume neither of these would prevent the engine from starting.

 

The only other clue is that when the engine starts, it sometimes runs unevenly for a few miles, as though the ECU was recalculating values and settings??

 

Any help or suggestions would be very much appreciated, I have been to two garages, paying twice now for diagnostics and they were unable to identify the fault.

[insider]

Engine speed sensor could cause the problem. The ECU needs to see a minimum engine cranking speed before the engine will start.