406oc.co.uk

hi guys as some of u know i had a problem with my hdi 110 on a 2000 plate starting when its warm well today the car was tok for a run then left too cool right down till the needle was at the very bottom no heat atall from the engine. i went to start it and it wouldnt start i had to bump start it i am gettin no fault codes the intank pump is fine the hp pump is fine as theres fuel gettin to the injectors. heres a list of what ive changed with new parts
crank sensor
fuel double relay
fuel pressure sensor
fuel filter
low pressure pump

i replaced the filter housing when i got the car as it was too tight to open and i couldnt change the filter so i got one from a scrap car was a bit hard to open but it still opened letting me change fuel filter but the metal ring that sits on the filter is all bent is it supposed to be like this could this be causing my problem not sealin correctly or letting in air

Have you changed the glow plugs at all? Also, I'm pretty sure the mis-shapen ring on the filter housing is meant to be there.

The mis-shaped bent ring was a right royal pain in the posterior when i finally got my fuel filter housing open, the new filter was not an oem one and stood maybe a millimetre or 2 higher in the housing than the existing one, now this might have been because the old one had squashed down over time in the housing or it could have been smaller when fitted.

what i did to get around this was cut a through the ring and file out maybe 2.5mm from the cut ends this let it compress a little easier and i could actually get the top on the filter housing properly then,

without the cut i couldnt get the thing to seal properly at all,
she ran and started fine and there were no problems with air getting in and that's how it ran for the last 2000 miles or so before the clutch gave in and i scrapped the old girl.

modified406 wrote:
i replaced the filter housing when i got the car as it was too tight to open and i couldnt change the filter so i got one from a scrap car was a bit hard to open but it still opened letting me change fuel filter but the metal ring that sits on the filter is all bent is it supposed to be like this could this be causing my problem not sealin correctly or letting in air

The metal ring is supposed to be bent to allow the lid to be held tight when you turn the nut, it's actually a spring locking ring.
If you had a leak on the filter housing you would get diesel flooding out under pressure, believe me I've seen them leak, diesel gets everywhere!

Regarding your bad starting, have you replaced the engine management coolant sensor? It could be sensing the wrong engine temperature.

ive replaced the engine temp sensor

little update on this regardless of whether the car is warm or cold

the car starts fine when the 2 passenger wheels are on the kirb it seems to start fine when the car is tilted if this makes sense could the low pressure pump be at fault here

its as if when the car has all four wheels on the road it seems that the lp pump is not sooking up enough fuel for it to start but if its sitten on the kirb with jst the 2 driver side wheels on the road it starts no problem

That do sound like it could be something to do with the lift pump, however they don't normally die like that. Can you hear it pressurising the system? Does it cut out after a few seconds?

Long shot, but could your tank vent be blocked? (try running it with the cap off for a bit).

steve_earwig wrote:That do sound like it could be something to do with the lift pump, however they don't normally die like that. Can you hear it pressurising the system? Does it cut out after a few seconds?

yes mate i can hear it running then cutting out after about 5 or 10 seconds if i had a spare locking ring ad take it out and check if theres a blockage

dogslife wrote:Long shot, but could your tank vent be blocked? (try running it with the cap off for a bit).

i will try that later on today will diesel not pour out of the cap though

i dont think my lift pump is ready to die i just think something maybe blocking it or something isnt opening up on the pump to let the diesel in

If the pump cuts out then the system is pressurised and ready to start. Although 10 seconds seems a bit long to me

When you turn the ignition on, I think it just runs for a fixed period, regardless of fuel pressure. (That's why you have to run it multiple times to prime, if you've run out of fuel).

IIRC, once the engine starts, lift pump runs continuously provided you have oil pressure.........

Have you proven you have power to the lift pump all the time, when the engine's running?

AH, so if it's timed then the system's not necessarily pressurised. Hold on a minute... My pump runs for 4 seconds. I can't imagine it would run for 4 seconds regardless of pressure so perhaps if Mr 406's pump is running for longer it would point to a blockage

steve_earwig wrote:AH, so if it's timed then the system's not necessarily pressurised. Hold on a minute... My pump runs for 4 seconds. I can't imagine it would run for regardless of pressure so perhaps if Mr 406's pump is running for longer it would point to a blockage

i think its a blockage as i dont think the pump is knackered the pump was replaced not long before i got the car the car was starting fine until i took the last injector rubber pipe off to see if there was fuel getting to them then after that it wouldnt start straight away like it used to do

dogslife wrote:When you turn the ignition on, I think it just runs for a fixed period, regardless of fuel pressure. (That's why you have to run it multiple times to prime, if you've run out of fuel).

IIRC, once the engine starts, lift pump runs continuously provided you have oil pressure.........

Have you proven you have power to the lift pump all the time, when the engine's running?

havent proven that mate how would i go about that

See if you can connect a small lamp between earth and either terminal 3 on your pump, or MF12 in the engine fusebox. (Should be possible to pull the fuse & carefully poke a fine piece of wire into the holder & refit the fuse to hold it in). Obviously you need to make sure you don't short anything out.....

This should tell you whether the pump gets turned off & stopping your engine.