General Non Starting Doblo Cargo 1.9 Multijet

[ChrisJ1973]

Hi Everyone, Long time reader but first time posting. I've searched the forum and found similar problems, and over the last few months i've been following the solutions, but non have worked and so I'm posting this in the hope that somebody can help?.

I have a non starting Fiat Doblo 1.9 Cargo Multijet on a 55 plate, and up to about 4 months ago it was running fine, then it began taking more and more attempts to start, often requiring several cranking attempts before it would start after which it would run from the first turn of the key all day, even when cold, until the next morning when it would be hard to start again.

Then one Afternoon, it just cut out at some traffic lights and wouldn't restart, and upon lifting the bonnet I found that diesel was leaking all over the engine. This was traced to a perished leak off pipe running between the end of the injector tops to the black fuel manifold box, which had swollen and become to wide for the connecting barb. This was replaced, along with the leak off pipes running across the tops of the injectors, and normal running was resumed, and the starting issue disappeared.

This lasted for about a week, when the hard starting returned, and then one morning it just refused to start at all, eventually flattening its battery and a booster pack. There were no error codes logged, so I tried replacing the most obvious things first, replacing the fuel filter, Fuel pump relay and then the Battery, but the problem still wasn't solved.

The in-tank pump is running and there is a good flow of diesel being pumped through the filter and into the intake side of the HP pump, but according to the running parameters the rail isn't seeing the pressure it needs to start during cranking. So I then replaced the following:-

Rail Pressure Sensor
PCV Regulator Seals replaced (Green and white washers on the spindle)
PCV Regulator ( New Bosch unit)
All low pressure fuel lines
Replaced metal high pressure Fuel Line between the HP Pump and Rail
Removed and cleaned EGR Valve

I've also done a physical leak off test on each injector using 4 bottles and tubes, and all fill slowly to within one mark of each other, there is no huge gush of fuel to indicate that there is an injector are stuck open.

(Cambelt was replaced and a Brand New set of Glowplugs fitted at the Start of the Year)

Non of the above have got it running, and there are still no fault codes logged with each attempt, then I noticed this weekend that despite the Starter Motor sounding like it is cranking fast and the Battery being brand new and fully charged, the cranking speed shown on the Software never seems to go much above 220 - 230 RPM. So my first question is, whether this constant upper cranking speed is OK?, as I'm sure that I read somewhere that the Fiat Diesel's need to crank above 250 RPM before the ECU increases the fueling and activates the injectors?. Is there any Truth in this? or is it just internet pub talk!?.

I also notice that during cranking the Battery Voltage hovers around 10.5v and often dips under 10v, after a couple of starting attempts from being fully charged. I admit that I bought a cheap Calcium style battery to replace the one which was on the Van when I bought it, but it has the same Capacity (60AH) and CCA (540A) and is the same size and i'm no wondering if its not up to the Job. I charged and refitted the old battery and even tried them both together (linked via Jump Leads) but the results are around the same.

After chasing after a fuel issue, Could it be the Starter Motor or Battery which is still at fault?. I've uploaded and linked to two screenshots showing the various parameters during two start up and cranking sessions to see if anybody has any suggestions?

https://ibb.co/2tQYF55

https://ibb.co/qNWhQ8b


In all honesty after trying to get it going again for nearly 3 months i'm ready to just throw in the towel, scrap it and replace it with another cheap van as a runaround, but bodywork wise its still in very good condition inside and outside compared to the endless dented rot boxes and builders' vans that i've looked at replacing it with, and having paid to get it ply lined a month before it started playing up, i'm a bit reluctant to give up on it! and so any help would be appreciated.

Thanks in advance

 

[dansar]

hi i'm not a mechanic but i do know i've had similar problems,i resolved mine by changing the fuel cut off switch just in the pilar drivers side page 69 of the doblo handbook,i think mine was faulty if you haven't checked this it's worth a try

 

[varesecrazy]

Hi Everyone, Long time reader but first time posting. I've searched the forum and found similar problems, and over the last few months i've been following the solutions, but non have worked and so I'm posting this in the hope that somebody can help?.

I have a non starting Fiat Doblo 1.9 Cargo Multijet on a 55 plate, and up to about 4 months ago it was running fine, then it began taking more and more attempts to start, often requiring several cranking attempts before it would start after which it would run from the first turn of the key all day, even when cold, until the next morning when it would be hard to start again.

Then one Afternoon, it just cut out at some traffic lights and wouldn't restart, and upon lifting the bonnet I found that diesel was leaking all over the engine. This was traced to a perished leak off pipe running between the end of the injector tops to the black fuel manifold box, which had swollen and become to wide for the connecting barb. This was replaced, along with the leak off pipes running across the tops of the injectors, and normal running was resumed, and the starting issue disappeared.

This lasted for about a week, when the hard starting returned, and then one morning it just refused to start at all, eventually flattening its battery and a booster pack. There were no error codes logged, so I tried replacing the most obvious things first, replacing the fuel filter, Fuel pump relay and then the Battery, but the problem still wasn't solved.

The in-tank pump is running and there is a good flow of diesel being pumped through the filter and into the intake side of the HP pump, but according to the running parameters the rail isn't seeing the pressure it needs to start during cranking. So I then replaced the following:-

Rail Pressure Sensor
PCV Regulator Seals replaced (Green and white washers on the spindle)
PCV Regulator ( New Bosch unit)
All low pressure fuel lines
Replaced metal high pressure Fuel Line between the HP Pump and Rail
Removed and cleaned EGR Valve

I've also done a physical leak off test on each injector using 4 bottles and tubes, and all fill slowly to within one mark of each other, there is no huge gush of fuel to indicate that there is an injector are stuck open.

(Cambelt was replaced and a Brand New set of Glowplugs fitted at the Start of the Year)

Non of the above have got it running, and there are still no fault codes logged with each attempt, then I noticed this weekend that despite the Starter Motor sounding like it is cranking fast and the Battery being brand new and fully charged, the cranking speed shown on the Software never seems to go much above 220 - 230 RPM. So my first question is, whether this constant upper cranking speed is OK?, as I'm sure that I read somewhere that the Fiat Diesel's need to crank above 250 RPM before the ECU increases the fueling and activates the injectors?. Is there any Truth in this? or is it just internet pub talk!?.

I also notice that during cranking the Battery Voltage hovers around 10.5v and often dips under 10v, after a couple of starting attempts from being fully charged. I admit that I bought a cheap Calcium style battery to replace the one which was on the Van when I bought it, but it has the same Capacity (60AH) and CCA (540A) and is the same size and i'm no wondering if its not up to the Job. I charged and refitted the old battery and even tried them both together (linked via Jump Leads) but the results are around the same.

After chasing after a fuel issue, Could it be the Starter Motor or Battery which is still at fault?. I've uploaded and linked to two screenshots showing the various parameters during two start up and cranking sessions to see if anybody has any suggestions?

https://ibb.co/2tQYF55

https://ibb.co/qNWhQ8b


In all honesty after trying to get it going again for nearly 3 months i'm ready to just throw in the towel, scrap it and replace it with another cheap van as a runaround, but bodywork wise its still in very good condition inside and outside compared to the endless dented rot boxes and builders' vans that i've looked at replacing it with, and having paid to get it ply lined a month before it started playing up, i'm a bit reluctant to give up on it! and so any help would be appreciated.

Thanks in advance

Hi. Is it still with you?

Charlie

 

[ChrisJ1973]

Hi. Is it still with you?

Charlie

Its a few days away from being disposed of, as i've now replaced it with another Van as getting a Diesel specialist to come out to it would probably cost twice what its worth.

The offending Van is about to be collected after Xmas by a Salvage Yard, and turned into a small cube of scrap. Can't wait to be rid of it now

hi i'm not a mechanic but i do know i've had similar problems,i resolved mine by changing the fuel cut off switch just in the pilar drivers side page 69 of the doblo handbook,i think mine was faulty if you haven't checked this it's worth a try

Sadly not, that was one of the first things I checked. But thanks for your suggestion.

 

[varesecrazy]

Does it go on easy start..

If it was purely struggling rail pressure due to low revs..
Then any kind of decent revs ( through towing.. or a substitute fuel source) should get the injection working

 

[bunterboy]

Crank shaft sensor £30 solved my dead doblo, similar probs to you.

 

[ChrisJ1973]

Thought I would give an update in case it helps anybody else googling with the same problem!.

Finally managed to get the Van going this afternoon. The problem turned out to be a jammed pressure valve on the inside of the inlet pipe to the high pressure injection pump. This is a spring loaded valve mounted halfway down the inside of the inlet pipe which opens when subject to fuel pressure from the low pressure pump and is apparently fitted to shut off the fuel flow into the pump if the pressure drops due to a fuel pipe / filter blockage or the LP pump failing whilst in use.

In my case the valve had jammed partially open, but not enough to let more than a dribble of fuel into the pump, hence why I was seeing low pressure when cranking, there simply wasn't enough fuel flowing into the pump to raise the rail pressure to where it should be.

The valve is not visible, as it is mounted halfway down inside the fuel inlet pipe, however gently poking a small, clean allen key down the inlet pipe on the pump will reveal it, and if it is working correctly you will feel resistance as the valve pushes downwards with pressure, and then it should spring strongly back when released. In my case the valve didn't move at all, it was stuck. Fortunately another gallery allows a small amount of fuel to flow around the moving parts inside the pump to prevent damage even when the valve is shut.

Soaking it for a few hours in neat Archoil AR6900 diesel additive, freed it up and returned the spring action with no sticking. I Connected the fuel pipe back to the inlet, allowed 15 seconds for the LP to prime the system (As when changing a fuel filter) and it started first time.

I'm told that this problem can sometimes be caused by a sticky varnish type residue in the fuel caused by poor quality fuel, water contamination or a diesel bug / algae forming in the tank, so as a precaution I used the lift pump to drain the tank into a container and have filled the tank with fresh fuel and added a biocide to kill off any bacteria in the tank.

Its taken over 8 months and a lot of head scratching to get the van running again, and I almost scrapped it for pennies purely down to a sticking valve. I thought I would put this up here as despite posting on several forums nobody offered this as a possible solution so I guess it isn't a well known issue, but may needlessly lead to the entire pump being replaced.

All of this was carried out with the pump fitted to the Van, and the only access required is to remove the clipped on fuel pipe from the inlet port on the IP, by pressing in the side clips and firmly pulling upwards, from here you can poke down into the pipe and check the correct operation of the valve.

 

[varesecrazy]

Top job there Chris.

Well done.

Glad we gave you the momentum to try again.

Charlie

 

[woolfie]

Thanks Chris this is the type of problem that needs to be shared and the resolution posted . I take my hat off to you for sticking with it (no pun intended).

 

[bunterboy]

Well done Chris, just spotted this, handy to know. Billy

 

[varesecrazy]

ChrisJ1973

Any updates..??

 

[ChrisJ1973]

ChrisJ1973

Any updates..??

Still on the road, passed its MOT with no advisories including the new, stricter smoke tests, not bad for a 2005 Van.

Only one problem since I got it going, the little valve inside the inlet pipe jammed again, about 4 months after I freed it up the first time resulting in the same non starting issue, however I just removed the inlet pipe, jiggled it with an allen key again, and got it going. I still think it may all be down to running it on cheap supermarket fuel, or a bad / stale batch of diesel but it has only returned again the once in the 12 months since I originally fixed it and I haven't switched to premium diesel.

I have also been periodically adding a diesel additive to the fuel since the second time it jammed, its called Keropur D manufactured by BASF

(I can't post URL's otherwise i'd put a link to the manufacturers website, but Google will find it)

You can buy original Keropur on Ebay and Amazon from a seller in Germany, however its also exactly the same as the BMW Diesel Additive, which is about Half the price and is just re-branded Keropur. No idea if the additive is actually helping and no proof its doing anything only that it hasn't jammed again. I found Keropur as it is supposed to be one of the strongest P.E.A based additives you can buy - stronger % than even the Archoil range, and these types of additives are supposed to be more effective at cleaning and maintaining fuel injection systems than the Solvent based additives, and so i'm purely using it in the hope it gets rid of any sticky fuel varnish residues left in the tank / fuel system / pump, which I believe may be the cause of the spring-valve sticking.

 

[varesecrazy]

Great to hear its still doing its stuff.

Yes algae and the like sounds a nightmare..

Did it sit unused at times?

My 1.3's do a regular run each week.. so I only fill to 1/3.. keeps it all pretty fresh.

All the best

Charlie

 

[patmor]

tried everything seen this post thought i would try it started straight away unbelievable
thank you very much
cheers
Mick