Technical Help, not starting since this this storm hit

[richieski]

Hi all, I have a 2018 doblo lwb 1.6 120.
It won't start, it turns over and tries to fire up but doesn't start.
Been running fine, starts 1st 2nd turn. Never had an issue with running or starting.
It's parked at an angle to the drivers side, there is a pool of water on the scuttle which i think is normal as there is no drain hole inthat bit.
The only diffence between yesterday and today is the weather.
I had it parked the other way before.
I have a xtool 7s diagnostic tool which is pretty good and didn't show any DTC.
I believe it could be something to do with the rain or could it be a coincidence?
I can check and record all types of data, any advice what to select and crank it to see if it has the correct parameters to start.
thanks

 

[varesecrazy]

Is the fuel pump whirring when you turn the. Key to MAR?

 

[varesecrazy]

Hi all, I have a 2018 doblo lwb 1.6 120.
It won't start, it turns over and tries to fire up but doesn't start.
Been running fine, starts 1st 2nd turn. Never had an issue with running or starting.
It's parked at an angle to the drivers side, there is a pool of water on the scuttle which i think is normal as there is no drain hole inthat bit.
The only diffence between yesterday and today is the weather.
I had it parked the other way before.
I have a xtool 7s diagnostic tool which is pretty good and didn't show any DTC.

Waxy diesel..?

 

[The Panda Nut]

Waxy diesel..?

Good shout. Whats the temperture there? I only experienced this once the car did start in the end but ran rough for 10 miles before it resolved. If in doubt use a hair dryer in the under bonnet fuel lines from and including the filter housing. I always ran with diesel antifreeze in cold weather after that. It seems to work. I found a batch vastly reduced and bought the lot. Citroen Antifigeant it was about 25p a litre if I remember right. Only last year gave the last can to my brother.

 

[richieski]

Is the fuel pump whirring when you turn the. Key to MAR?

Good point i will go and listen now, I did remeber i has a similar issue on my v6 diesel audi. Drove perfect, pulled up onto drive and it would not start again. Turned out to be fuel pump.

 

[richieski]

Good shout. Whats the temperture there? I only experienced this once the car did start in the end but ran rough for 10 miles before it resolved. If in doubt use a hair dryer in the under bonnet fuel lines from and including the filter housing. I always ran with diesel antifreeze in cold weather after that. It seems to work. I found a batch vastly reduced and bought the lot. Citroen Antifigeant it was about 25p a litre if I remember right. Only last year gave the last can to my brother.

It's above 10 deg so not cold

 

[richieski]

Fuel rail pressure reaches 600 bar but drops right off after cranking. Cranks about 680 rpm at the peak point

 

[The Panda Nut]

It's above 10 deg so not cold

OK not waxing then. I suspect its coincidence though. If the diesel turns over (and fast enough) and it has fuel it almost has to run. I dont like Easi start but this may be a case of giving it a sniffter and see what happens. I would check the air filter is dry and hasnt got soaked somehow. My Bravo had the air filter in teh front wheel arch behind the liner. I once found it was a mush. Of course the elephant in teh room is heater plugs but at 10C and with a modern engine this isnt the problem it was once.

 

[richieski]

Will try easy start , pissing down currently though. Bad timing broken van and bad weather.

 

[varesecrazy]

View attachment 455834

Fuel rail pressure reaches 600 bar but drops right off after cranking. Cranks about 680 rpm at the peak point

It maybe a leaky injector..

The ECU needs to see High pressures in the rail or it won't permit injection

IF it runs briefly.. See what rail pressures show then

 

[richieski]

It maybe a leaky injector..

The ECU needs to see High pressures in the rail or it won't permit injection

IF it runs briefly.. See what rail pressures show then

It does not run briefly, just will not fire up. I left it for half hr and tried it and it felt like it almost started but every try after was nothing. I need to go listen to the fuel pump. Problem is i have draws etc fitted.

 

[richieski]

OK, so left it for abot 1.5hrs. Key to pos II. Can't hear the fuel pump. Rain doesn't help but pretty sure you can normally hear it whirl. It fired up on 1st turn for about 2 sec then died. Does feel like it was starved of fuel.
So i guess i need to check voltage at the fuel pump.
Does anyone have a diagram or measurements as to where the pump is? I have a ply floor and other bits on top so would be easier to use multitool to cut a hole. I guess they have a lft pump at the tank , not sure if high pressure is electrical or mechanical.

 

[richieski]

It's the multijet 2, does anyone know if which is the pipe from the tank at the fuel filter? I guess if i take that off and crank it then i'll see fuel coming out.

 

[richieski]

Ok so not the lift pump, lots of fuel before and afrer filter.
I can do a leak back test, does anyone know what the rail pressure is during cranking?
I have just noticed some foam has been chewed off 1 of the fuel pipes by a rat, bits on top of the air box. Hope it hasn't chewed through something.
Again came home and it started for 1-2 seconds.
Any ideas?
I guess i can't check fuel correction levels unless its running.

 

[The Panda Nut]

You need a diagnosis. Fuel raiI pressure sensor or wiring now look under suspicion. If it ran ok before and in view of rodents involvemebt even more so. The fact it starts lead me away from injectors.

 

[richieski]

As in the previous pic of the graph,the rail pressure reaches 600 bar at cranking. My friend just tested his traffic and that reached 300 bar for a turn when it fired it went down to 250 bar when running.
I need to know what pressure at cranking should be . If 600 is too high will it cut of the fuel? I need to check the fuel cut off relay is not energised etc
I disconnected 1 injector at a time to see if 1 was open causing pressure drop but no difference.

 

[richieski]

Just found this statement

• The pressure to deliver fuel from the high pressure pump to the rail/injectors at cranking is around 200 bars, at idle the pressure should be around 300 bars. When the vehicle is running the pressure ranges from 1200 bar to 2000 bar.

 

[richieski]

So is my 600bar due to faulty sensor or can the pump push 600 when cranking

 

[richieski]

Just tested the rail pressure sensor, i'm not getting any continuity between any of the pins indicating open circuit. Will check diagram. Would bridging the Perm +5v to the sensor (return) line potentially bypass the sensor?

 

[richieski]