Technical 1.3 Multijet smoke problem when at operating temperature

[Adamnikk101]

Hi everyone,
I’m looking for some advice regarding an issue with my 1.3 Multijet diesel (2011, Euro 5). I’ve been dealing with intermittent blueish smoke, and I’ve tried a number of things already, but I’m still not 100% sure what the root cause is.
Here are the symptoms:
The car does NOT smoke at all when cold
Once it reaches operating temperature, it starts producing blueish smoke, but only under acceleration (no smoke at idle)
The exhaust tip gets oily
The engine runs well overall, starts fine, and has good power
No excessive blow-by from the dipstick, but a little smoke comes out
Additional observations:
At one point, the oil level increased (smelled like diesel), then later started dropping
There is a noticeable smell of both oil and diesel from the exhaust
With the MAF sensor unplugged, the smoke seems somewhat reduced
One cylinder/exhaust port appeared oily compared to others
Work already done:
Injectors removed, cleaned, and seats cleaned
New copper washers and seals installed
Oil and filter changed
New turbo put
Other notes:
Turbo actuator moves normally on ignition
No major vacuum issues noticed, although I can hear some whine noise when rpms start dropping from like 1500 to 1000 rpms
Engine behavior slightly changes after a few minutes of idling (sound difference)
My concerns / questions:
Could it be that DPF is only physically removed but not remapped the ECU?
Could this still be injector-related (overfueling or leaking injector)?
Is it possible that piston rings are sticking or worn, even though there’s no smoke when cold?
Could the turbo be passing oil only when hot/under load?
Does fuel dilution of oil point more toward injectors or high-pressure pump issues?
I’m trying to decide whether it’s worth attempting ring cleaning treatments or if I should prepare for a more serious repair.
Any insights or similar experiences would be greatly appreciated.
Thanks in advance!

 

[bugsymike]

Hi everyone,
I’m looking for some advice regarding an issue with my 1.3 Multijet diesel (2011, Euro 5). I’ve been dealing with intermittent blueish smoke, and I’ve tried a number of things already, but I’m still not 100% sure what the root cause is.
Here are the symptoms:
The car does NOT smoke at all when cold
Once it reaches operating temperature, it starts producing blueish smoke, but only under acceleration (no smoke at idle)
The exhaust tip gets oily
The engine runs well overall, starts fine, and has good power
No excessive blow-by from the dipstick, but a little smoke comes out
Additional observations:
At one point, the oil level increased (smelled like diesel), then later started dropping
There is a noticeable smell of both oil and diesel from the exhaust
With the MAF sensor unplugged, the smoke seems somewhat reduced
One cylinder/exhaust port appeared oily compared to others
Work already done:
Injectors removed, cleaned, and seats cleaned
New copper washers and seals installed
Oil and filter changed
New turbo put
Other notes:
Turbo actuator moves normally on ignition
No major vacuum issues noticed, although I can hear some whine noise when rpms start dropping from like 1500 to 1000 rpms
Engine behavior slightly changes after a few minutes of idling (sound difference)
My concerns / questions:
Could it be that DPF is only physically removed but not remapped the ECU?
Could this still be injector-related (overfueling or leaking injector)?
Is it possible that piston rings are sticking or worn, even though there’s no smoke when cold?
Could the turbo be passing oil only when hot/under load?
Does fuel dilution of oil point more toward injectors or high-pressure pump issues?
I’m trying to decide whether it’s worth attempting ring cleaning treatments or if I should prepare for a more serious repair.
Any insights or similar experiences would be greatly appreciated.
Thanks in advance!

When I first read , I thought DPF Regen, but you say it has been removed.
Re the turbo and oil, can you feel excessive movement on the impeller when you remove the air intake?
I had a 1.6 MJ Fiat Doblo with worn turbo and replaced the cartridge part, it still smoked for some time due to oil in the intercooler, whilst testing for this I removed the intake pipe just before the intake manifold and ran the engine including bringing up the engine revs whilst carefully holding a piece of A4 paper in front of the outlet from the turbo pipe which I had angled away from the inlet manifold, eventually when turbo and intercooler had cleared all the oil then the A4 paper would be clean of oil spray/particles. If yours is clean then it would indicate that oil is not coming from turbo, but may be worn piston.
Inciderntally check for oil in the air filter inlet side as if engine pistons worn it may push opil/fumes into the breather pipe and then into turbo from that side.
Note when doing this test the engine will not rev as good as usual due to no turbo boost, also it may produce error codes, these can be deleted.
If you suspect piston wear on a single piston that is showing signs of oil on manifold etc. I usually do a "leak test" involving compressed air and an adaptor via the heater plug or injector hole with threaded connector. Note "leak test" not "leak off test" as that is for testing injectors.
If doing this test be very careful nothing gets sucked into the inlet manifold or you will destroy the engine!

 

[Adamnikk101]

When I first read , I thought DPF Regen, but you say it has been removed.
Re the turbo and oil, can you feel excessive movement on the impeller when you remove the air intake?
I had a 1.6 MJ Fiat Doblo with worn turbo and replaced the cartridge part, it still smoked for some time due to oil in the intercooler, whilst testing for this I removed the intake pipe just before the intake manifold and ran the engine including bringing up the engine revs whilst carefully holding a piece of A4 paper in front of the outlet from the turbo pipe which I had angled away from the inlet manifold, eventually when turbo and intercooler had cleared all the oil then the A4 paper would be clean of oil spray/particles. If yours is clean then it would indicate that oil is not coming from turbo, but may be worn piston.
Inciderntally check for oil in the air filter inlet side as if engine pistons worn it may push opil/fumes into the breather pipe and then into turbo from that side.
Note when doing this test the engine will not rev as good as usual due to no turbo boost, also it may produce error codes, these can be deleted.
If you suspect piston wear on a single piston that is showing signs of oil on manifold etc. I usually do a "leak test" involving compressed air and an adaptor via the heater plug or injector hole with threaded connector. Note "leak test" not "leak off test" as that is for testing injectors.
If doing this test be very careful nothing gets sucked into the inlet manifold or you will destroy the engine!

I am actually not sure if it has been removed as it should. On diagnostic it says something like Total DPF regeneration count to be above 1000 times. And the car has 209k km, thats a good amount. Or it may could that previous owner drove it too much with clogged dpf and screwed the piston rings...

 

[bugsymike]

I am actually not sure if it has been removed as it should. On diagnostic it says something like Total DPF regeneration count to be above 1000 times. And the car has 209k km, thats a good amount. Or it may could that previous owner drove it too much with clogged dpf and screwed the piston rings...

A good diagnostic tool should tell, also if you do a physical check to see if DPF and it's pressure sensor pipes are still connected and see if unplugging it brings up error codes or changes any pressure readings of DPF. What usually happens is the sensor reads pressure before and after the DPF to tell how restricted it is and calculates the amount of blockage/soot content in the DPF. If the DPF had been removed internally but left sensors in place then readings in and out would be the same, this may cause error codes anyway unless it has been deleted in the ECU I think, but not something I have done.
I did have a severely clocked DPF on a Citroen Picasso 1.6HDI with 220,000 miles on it, I was able to rfemove and clean the DPF and refit to vehicle and then used diagnostics to tell the ECU it had been replaced, it lasted another 4 years with no problems.
Going back to your previous post oil level rising and smelling of diesel is a common issue with failed DPF Regens as ECU puts extra diesel in to make exhaust hotter to do the Forced Regen but if conditions stop it from working several times, all that diesel runs into the sump of oil.