Doblo Hi

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Doblo Hi

Had it in for MOT today and it passed ! I was very surprised! I think the Turbo is knackered though as there's a lot of oily smoke coming from exhuast however no turbo whistle .The starter motor packed in during MOT aswel but hopefully just solenoid sticking . Changed out the Filters today and Oil change . She's still not starting but Hope tomorrow get the milticuscan through the post and see what's going on, although the snap on reader never picked up any codes !
 
So had the multiecuscan on it and no codes . Not sure how I get the rail pressure reading ?
Got a new starter Motor and still no start !
I tried to release any air trapped in fuel system by loosening the fuel rail unions and still she won't start !
Is there away to test the HP Fuel Pump ?
 
So had the multiecuscan on it and no codes . Not sure how I get the rail pressure reading ?
Got a new starter Motor and still no start !
I tried to release any air trapped in fuel system by loosening the fuel rail unions and still she won't start !
Is there away to test the HP Fuel Pump ?

Hi,
In MES connect to the engine ECU and then click the "parameters" box (or press F4) and you will get a list of values you can display including fuel pressure, required fuel pressure, sensor signal etc. You have to click the check box to the left of the parameter to make it display.
Sorry for slow replies I've been in the USA but home now.

Robert G8RPI.
 
Hi ,
Hope you enjoyed the states? I've never been myself but hopefully one day I'll get there .
So today I was looking up YouTube videos for fuel rail sensors and how to test them . Whilst I was testing the Back and white wire I noticed that I do not get any voltage at all . I have tried to start engine and no voltage . According to the RAC guy on the video he said that I should be getting around 0.21 whilst ignition to on position and 0.94 whilst engine on . So does anyone have any idea where this wire comes from ?
Also as the picture above on the fuel pressure suggests I am not getting enough pressure at start up . I should be getting 282 bar but only getting 8 bar ? Not sure where to go next ?
Thanks
Graeme
 

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Hi,
the USA trip was work but a training course so not too bad.
Looks like you need a replacement fuel pump. However the sensor signals look wrong.
The connections (for a 1.9 16V sensor ) are
1 - Earth
2 - Output signal
3 - Supply
The supply is normally 5V and comes from the ECU. You appear you be on pin 3 of the sensor. You need to check the wiring diagram for your car but on the 16V it goes to pin 4 of connector B on the ECU.

As the car has been messed with it could even be the wrong connector for the sensor. You could check that by seeing if the pressure reported by MES changes when you un-plug the connector. Someone may have changed wiring to hide a worn pump.

It's very hard to fault find on a car that has been messed with, even more so remotely. I'd want to check ALL the wiring and connectors before spending money on parts.


Robert G8RPI
 
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Thanks for replying Robert .
I will check the wiring out . What is connector b of ecu? Is that the one on the right or left ? Thanks
 
I unplugged the connector , and the MES said desire pressure 350 bar and current pressure was 350 bar .
When I connected it back up pressure went down to 6 bar.
Once I was turning it over the max pressure got to 118 bar , so well short of 350 bar.
Got a second hand pump coming tomorrow ( Hopefully) if that does not solve it ten I think I will just sellotape straws from the steering wheel to the air-intake and just spray easy start every time ! Haha
 
So today I changed over the HP pump and gues what ? It still not starting on it's own !
So I need to look at a similar Doblo to check where all these loose connections go too ?
Next step is a different ecu me thinks
 
As somebody mentioned, an air leak can cause difficult starting. Try looking at the vacuum tube from the MAP (I own a Cinquecento, not a Doblo..) to check that it isn't split or perished.

Suspect the MAP itself. Try disconnecting the electrical connector and see if the car will start. A MAP can cause all manner of starting and running problems which don't always result in an error code.

To check if the inlet manifold is leaking, spray some wd40 around it - and get somebody to crank the car while you spray that area. The idea is that the wd40 will create a brief seal and hopefully allow the car to start (and cause a cloud of blue smoke when it starts..).

Many many years ago I had a diesel engined Sherpa. It really was a nightmare to start, yet once started it ran fine and would immediately restart without any problem.

The problem came down to the heater plugs. A neighbour removed them and tested them against the battery using jump leads. They got hot quickly ... but lo and behold, that was with them removed from the engine. The actual fault was a corroded power cable to the heater plugs.

The fact that you get no error codes or warning lights on the dash tends to suggest it's related to air/fuel .. Regarding my Sherpa van, I'd visited a few diesel specialists who couldn't trace the problem. It wasn't until I followed the wire from the heater plugs to underneath a plastic cover and found the corroded-through cable.

Your air/fuel may not be getting heated at start up .. hence the reason you need the can of easy start/bump start.

It's always the simplest of problems that cause the biggest headaches.

Good luck .. and keep us updated.
 
Thanks mate , I will give that s go today . I have already tried to stay it with the connector unplugged but I will try again today . I'll keep you updated .
Graeme
 
Just as an afterthought ... I once had a Ford Escort diesel that developed an-almost-impossible to start problem.

The fault was the injectors. They weren't 'sticking' or blocked - they were actually worn. Where the nozzle fits to the body ... the body had become 'dished' because of being worn away by compression/fuel spray. If it hadn't been for somebody pointing it out to me I wouldn't have noticed or realised.

The image below is of a diesel injector (not your particular injector). I've drawn an arrow where the wear - the 'dishing' occurs.
 

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We've got a fiamma f35 awning to fix on our doblo with pop up roof does anyone know which fixing brackets we need? Tia
 
Just an update on my Doblo ,
So after changing fuel filter , fuel pump and hoses and god knows how many hours I have finally fixed it although not sure how exactly!
I unplugged all sensors that I could find and sprayed them with WD40 contact cleaner , plugged them back in and it started and has been starting ever sinnce !

Thanks to everyone here for their help .
 
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