Technical Fiat doblo running issues

[Karlpegler]

Hi, wanted to ask anybody for some advice. Purchased a 64 plate fiat doblo 90 multijet 1.3 with 101.000 miles.
My Vauxhall combo 1.3 was wrote off, same engine van ran great. My doblo has a faulty thermostat I’m changing soon. As it doesn’t hold temp well. But that’s unrelated to the doblo other issues. Cold starts fine. But once warm trying to start her up becomes harder. Turns over longer and a sluggish start. Only when warm or hot. If I stop the engine immediately and turn on its fires straight up. Seems to be if I park up run into a shop then try it’s harder to start. The other issue is one drive in maybe 15/20 the engine sound very rough and loud, and get blue smoke flying out the back. If I pull over and restart engine it’ll sort itself out and run fine again. Unsure where to start with these, anyone had similar issues ?

 

[bugsymike]

Hi, wanted to ask anybody for some advice. Purchased a 64 plate fiat doblo 90 multijet 1.3 with 101.000 miles.
My Vauxhall combo 1.3 was wrote off, same engine van ran great. My doblo has a faulty thermostat I’m changing soon. As it doesn’t hold temp well. But that’s unrelated to the doblo other issues. Cold starts fine. But once warm trying to start her up becomes harder. Turns over longer and a sluggish start. Only when warm or hot. If I stop the engine immediately and turn on its fires straight up. Seems to be if I park up run into a shop then try it’s harder to start. The other issue is one drive in maybe 15/20 the engine sound very rough and loud, and get blue smoke flying out the back. If I pull over and restart engine it’ll sort itself out and run fine again. Unsure where to start with these, anyone had similar issues ?

Just a thought when hot and not starting then loud and smoke, does it sound/feel slightly like a flat battery?
Leaky injectors can cause that, due to causing a slight "hydraulic lock" symptom.
Another clue is oil in sump level high and smells of diesel.

 

[Karlpegler]

It’s had a new battery and all injectors changed. So ruled those out.

 

[bugsymike]

It’s had a new battery and all injectors changed. So ruled those out.

New or rebuilt injectors?
What about the oil side I mentioned?
Any diagnostic codes to give a clue?
Why was battery changed?
Was it slow turning over as this could have damaged the starter meaning it doesn't spin as fast as it should?

 

[Karlpegler]

They were new injectors, no codes, oil level perfect, my Vauxhall combo was wrote off. But I had just bought a new battery for it. When I bought the doblo I shoved the new battery in that instead. Peace of mind. Started motor seems fine. Turns over good speed. When it’s having trouble starting when hot the starter speed is good. Is a very lumpy start. Cleaned maf and map sensors but they looked good. Sometimes I hear a whining noise when pressing accelerator. So I started to think is it turbo related or high pressure fuel pump. But all live data on fuel and rail pressure and injectors is great. Turbo pressure is a very small amount down.possibly a small air leak. But can’t find it. But my combo also had a worse boost leak and still started great.

 

[bugsymike]

They were new injectors, no codes, oil level perfect, my Vauxhall combo was wrote off. But I had just bought a new battery for it. When I bought the doblo I shoved the new battery in that instead. Peace of mind. Started motor seems fine. Turns over good speed. When it’s having trouble starting when hot the starter speed is good. Is a very lumpy start. Cleaned maf and map sensors but they looked good. Sometimes I hear a whining noise when pressing accelerator. So I started to think is it turbo related or high pressure fuel pump. But all live data on fuel and rail pressure and injectors is great. Turbo pressure is a very small amount down.possibly a small air leak. But can’t find it. But my combo also had a worse boost leak and still started great.

I agree about turbo not affecting starting as no or low boost at cranking speed.
Many of the usual starting issues on those small diesels are related to cold starting unlike yours.
With the not hot starting and engine sounding rough loud and blue smoke occasionally I have had that on customers vehicles where head gasket seeps water in or a leaking injector diesel, in both cases it increases the compression or even "hydraulic lock" so if/when it starts it tends to sound odd and chuck smoke out.
As you don't appear to be getting any of the other symptoms that sounds unlikely.
Perhaps others on Forum can suggest something else they have come across.

 

[Karlpegler]

Yeah it’s a weird one, I never get smoke on startup, even the hot tough start up. Just randomly now and again I’ll be driving and I’ll hear a humming noise followed by a louder engine and blue smoke. Turn engine on and off and it’ll go away and be fine again. I think maybe two different issues. I thought it was a dpf Regen but maybe some oil is passing by turbo seal and into the dpf hot side.but computer tells me last regen was successful 135 miles ago and this happened 20 odd miles ago.

 

[bugsymike]

Yeah it’s a weird one, I never get smoke on startup, even the hot tough start up. Just randomly now and again I’ll be driving and I’ll hear a humming noise followed by a louder engine and blue smoke. Turn engine on and off and it’ll go away and be fine again. I think maybe two different issues. I thought it was a dpf Regen but maybe some oil is passing by turbo seal and into the dpf hot side.but computer tells me last regen was successful 135 miles ago and this happened 20 odd miles ago.

How about the throttle body butterfly sticking, isn't that used to kill the engine?
Though I would have thought some kind of error message would appear.

 

[Karlpegler]

I know when I took it back under warranty he put 4 new injectors in and cleaned the throttle body. I saw him do it all whilst I waited. He thought one of those two things. But upon calling him yesterday he thinks it’s just the dpf regenerating now.

 

[Karlpegler]

Part of me wants to replace turbo, hp pump and throttle body. I have a turbo spare at home. Cant be too much for the rest

 

[bugsymike]

Part of me wants to replace turbo, hp pump and throttle body. I have a turbo spare at home. Cant be too much for the rest

Re the regen side it can sound different when trying to regen but I can't see that stopping it from starting unless totally blocked, but as you mention it runs OK normally and no error codes.
Surely HP pump would be a permanent issue not intermittent?

Part of me wants to replace turbo, hp pump and throttle body. I have a turbo spare at home. Cant be too much for the rest

Is it possible with pipe off to see operation of throttle body?
I know they don't like being pushed or forced to open whilst cleaning.
The only one I got away with that was on a older Kia Sportage that was vacuum operated and responded well to freeing off and cleaning, but in fairness the issue was just very gutless most of the time.

 

[Karlpegler]

Think I’m going to try take it off this weekend and have a look. May also disconnect turbo from dpf and have a look for oil, try see what I can rule out etc. I’ll report back if I find anything out. Appreciate your time Mike