starting

[lambert]

Hi all,

First thing in a morning my 300 takes a while to fire, if it gets 2 or 3 bursts of the heater plugs it is much better. It has been like it since I got it. It has a new Delphi lift pump and I can't find any splits or such in any fuel lines. It had never not started but it hardly jumps off the key. All subsequent starts on the same day are straight away unless it has stood all day but even then it is not that bad.

Any thoughts or ideas?

[Saffy]

battery could be weak, with pretty low crank current first thing in morning (possible being drained by something over night) so poor start, get's a boost from use during day so starts easier.
with a healthy and correct specification battery mine starts on a cold morning with the turn of key and with possible 3 engine revs ...so a couple seconds in all. BUT if I switch into the circuit my huge 2nd battery so that both battery are supplying the cranking then the engine starts instantly on key turn. So available cranking amps is a big factor in the ease of starting.

BTW the glowplugs do not seem to play much of a role in the 300tdi's I have had.

The mrs 300tdi disco has other issues with cold starting which stem from bug in it's engine management (its a fly by wire auto). It needs to be tricked into thinking it's always doing a very cold start so that it changes the pump timing accordingly else it just wont start without huge battery killing cranking times. I did a mod to achieve this which adds resistance into the temp sensor whilst the glow plug timer is active..... gives the servo in I/P pump some time to set and truck then starts on the key turn (it also has dual battery fitted so that helps too). After the timer drops out the resistance is removed from circuit and the sensor is back to telling the CPU the truth thus not using more fuel than needed (if the resistance was left in permanently then fuelling would be forever rich).

[lambert]

The battery is fit enough it spins it up easily it just seems that the first start takes longer than any other to catch. Also if I spin it and it does not catch but spin it again immediately then it catches first turn, though if I do that rather than hit the plugs I get a considerable amount of smoke which suggests I'm not lacking fuel on start up.

[LandRoger]

My 200tdi Disco and 200tdi 90, both started at first touch of key and revved cleanly straight away, my 300tdi Disco was okish with a burst of heat, my P38 2.5 dse is dire and makes me wish they had fitted a Tdi instead of Beemer lump thats not up to the job, its going this week for a Mitsi L200 twin cab whilst i have a Landy rethink, ,

[lambert]

Yeah my old disco went straight off the first twist, hence thinking the fender to go the same.

[lambert]

Right. Update I now have an optima red top battery and fresh glow plugs and it is getting better but not massively. Am thinking new fuel lines in rubber. Are any pipes more prone to failure than others?