C5 mk 1 starting problem

[CitroJim]

An HDi, in common with DI engines generally, will not need glowplugs to start unless the temperature is very, very low and much lower than ever experienced in the UK. Glowplugs on the HDi are there really only for post-heating after the engine initially starts to ensure smooth running and lower emissions during the warm-up period...

If it was low compression causing the issue you'd see white smoke (unburned fuel vapour) issuing from the exhaust whilst cranking... It would be good to get an observer to check for this just to definitely eliminate it as it may not be visible via the rear-view mirror.

If not that, the first port of call for me would be to check the low pressure pump in the tank is good and getting the fuel to the high-pressure pump promptly and checking that the filter housing is full of fuel before a start attempt just in case the filter housing is emptying and taking a while to fill and re-prime the fuel system... If it was empty then the high pressure pump would be drawing air and then when fuel does come through this air would need to be purged from the fuel rail and injectors.... A hard start and then a cloud of smoke would be the result of all of this...

Does it start OK for the rest of the day after the initial difficult start?

[hirsty]

Hi Jim - starting after the initial problem start is fine with no hesitation or extended cranking even after several hours standing. The fuel filter has been modified to a Rover throwawy type and has inlet and outlet at the top. Would it be worthwhile fitting a non return valve to the inlet side? Since tightening the fuel connections today, the car seems to run better (maybe a trick of the mind or wishful thinking).

hirsty

[CitroJim]

What exactly is a Rover Throwaway type filter Hirsty?

Why did you modify it? There might be the root cause of the issue perhaps....

[hirsty]

I didn't modify it. It was like that when I bought the car from howiedean. It is like the oil filter. Instead of removing the filter inside, the whole unit is changed. I didn't have this problem last winter even on below zero days. Should I change it back to the original?

hirsty

[CitroJim]

I see... Might be worth swapping the cartridge then, just to eliminate it...

Should I change it back to the original?

Depends entirely on why Howiedean changed it in the first place...

If it's easy to do and all is still in-situ then do as a test but put a new filter element in first...