Technical P0520 fault will not go away & everything changed

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Technical P0520 fault will not go away & everything changed

raindropsies

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I have a 1.3 diesel multijet Qubo (55kw)
I have the error code P0520, and check engine message
I have changed the 3 sensors relating to oil pressure sensors/switches, changed oil pump, changed timing chain, done full oil change, oil filter, in fact everything I can think of on the oil side and sensor/switches side to do with oil pressure switches/sensors
The code has been cleared several times but still comes up.
Can anyone please help with me getting this fixed, its only done 70k
Many thanks in advance
 
So when it had an oil and filter change. What did the degradation counter say?

And did it reset ok.? I suspect this may be related to your issue. :(

Oil degradation was reset fine

So an update but issue still exist

Oil pump, filter, sensors, switches, timing chain, oil,
Oil pressure test done and as it should be, its been "graphed" cold and hot and both show as they should so myself, 2 garages are now baffled as to what can be done, it's been to a specialist diagnostic place (not fiat) as the fiat one said they had this before with a previous qubo and were unable to fix, but the diagnostic garage its just been to is unable to map the code out

Feel like hitting my head on a wall now can anyone suggest anything that has not been done so this can be fixed, the car runs as it should just very annoying to have the engine light on and display say insufficient oil pressure to start with and then goes to say stop start unavailable
 
Only thing I can think of is (remembering a Mini from decades ago...) take out the pressure switch and check it's not gunked up.
In those days it gave a bad reading of blocked filter (I presume?) no computer to throw a wobbler at you, you just took things apart and cleaned them!

Worth a shot if you can find it.

R-V-M


Oil degradation was reset fine

So an update but issue still exist

Oil pump, filter, sensors, switches, timing chain, oil,
Oil pressure test done and as it should be, its been "graphed" cold and hot and both show as they should so myself, 2 garages are now baffled as to what can be done, it's been to a specialist diagnostic place (not fiat) as the fiat one said they had this before with a previous qubo and were unable to fix, but the diagnostic garage its just been to is unable to map the code out

Feel like hitting my head on a wall now can anyone suggest anything that has not been done so this can be fixed, the car runs as it should just very annoying to have the engine light on and display say insufficient oil pressure to start with and then goes to say stop start unavailable
 
Hiya

History:

Had a suspected 'timing chain jump' - lost power, limped home, ground to halt. No start. Horrendous rattle from the timing chain so ... a jumped tooth/messed timing?

Stripped it all down (what a palaver!!)

Turned out to be disintegrated guide rattling about & stretched chain - did the chain, guides etc. and in the process checked the oil pump (as you do) primed on the bench, seemed fine... Rockers OK. Reassembled.

Oil change, new filter. No leaks.

Still no start... eventually, worked through every sensor till I got to the fuel rail sensor. Changed, started, runs sweet as... till warm, then drops to limp mode 'check engine'

MUltiscan 'DPF clogged - level 2'. Passive regen... 100% So 'all good' (Runs through all revs like new). Stop. done.

But no! Start again runs with no warnings till around 50deg. (warm) then 'insufficient oil pressure' on the dash. What!!?

Run with Multiscan - anything around (or over) 1K rpm = Oil pressure 'normal' below that Oil pressure 'off' and 'insufficient oil pressure' on the dash

So, pulled pressure sensor - not stuck. Working.

Connected oil pressure gauge. At idle - swings between 0 and 3bar!

Hmm, baffled.

Possibly 'oil pressure regulator valve'? (this has the wretched stop-start)

80K

New injectors in the same month (1 over-fueling so changed the lot)
 
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A very long shot, but have any of you with this issue tried changing your oil cap? I did an oil change on mine today and unintentionally started it with the oil cap off. Straight away the cooling fan came on even though it was cold, but it went off as soon as I refitted the cap so the ecu must have somehow detected the cap was missing.

The cap has an O ring on it, come to think of it so does the dipstick. Is it possible that if the seal is perished or missing is it possible it could have an effect on the oil pressure???
 
Back on the 'boulder up a hill' again this am. latest:

Start - straight to 3 bar. No variance with revs. Hot or cold.
and/or
Start - stays at 0 bar till rev, then straight to 3 bar.

Urgh...

Thinks - sticking pressure relief valve? Hooray, turns out to be the only thing easily accessible on this wretched vehicle.

But boo, not obviously stuck, though plunger doesn't 'drop out' due to gravity which I (and my wonderful 'on the end of a phone' mechanic Dan at JD Auto Kings Lynn - did the injectors and an absolute gent on this) think it should.

Also, Qubo should idle at around .5bar and up to 4bar under revs, so consensus is now knackered oil pump - possibly distorted timing cover on re-fitting binding the relief valve 'just enough. (Now, try finding' a 'unique to 2011 models with stop-start' timing chain cover/oil pump... Why Fiat, just why!!? :bang: Pump on way from Czech republic...)
 
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I hope you are making progress RoyAB. Apologies for not checking in so often... I see your last update was three weeks ago.

When we owned a Peugeot HDI diesel, we has a really annoying fault that took some time to understand. Sometimes is worked fine, sometimes it went into limp home mode. Someone else had a similar issue nearby and we ended up comparing the cars side by side.

The fault turned out to be a vacuum leak on the sensor side.
A worn diaphragm had pin holes that lost vacuum and depending on where you were in your driving cycle it might make the difference between enough vacuum to operate a lever or none at all.

I don't know enough about the engine yet, but perhaps the you have a root cause that shows different fault modes depending on external conditions.

Anyone got a diagram of the sensors/actuators involved and how they sense/actuate?

I hope that helps - I know from experience that these issues can drive you mad. :mad:

Keep posting updates...Good luck
C.T.
 
I have a 1.3 diesel multijet Qubo (55kw)
I have the error code P0520, and check engine message
I have changed the 3 sensors relating to oil pressure sensors/switches, changed oil pump, changed timing chain, done full oil change, oil filter, in fact everything I can think of on the oil side and sensor/switches side to do with oil pressure switches/sensors
The code has been cleared several times but still comes up.
Can anyone please help with me getting this fixed, its only done 70k
Many thanks in advance

I know this is a fairly old post now but have you been able to shed any light on this problem??

I too have a 2011 Qubo 1.3MJ and have the same code as you and mine has just done 57K and fully serviced every year.
A mobile mechanic told me it's defo the oil pump BUT I took it to a trusted local garage for a second opinion and he is sure it's not the pump.

I have it booked in with FIAT on Monday 17th August to see what they say.
 
I know this is a fairly old post now but have you been able to shed any light on this problem??

I too have a 2011 Qubo 1.3MJ and have the same code as you and mine has just done 57K and fully serviced every year.
A mobile mechanic told me it's defo the oil pump BUT I took it to a trusted local garage for a second opinion and he is sure it's not the pump.

I have it booked in with FIAT on Monday 17th August to see what they say.

What is the oil pressure reading ?
RoyAB had it checked.. pressure good :)
But fault was only showing periodically

Is yours like this?

Couldbe a bad electrical connection..

See the above link ;)
 
What is the oil pressure reading ?

RoyAB had it checked.. pressure good :)
But fault was only showing periodically

Is yours like this?

Couldbe a bad electrical connection..

See the above link ;)

Hope Fiat will check pressure but no oil light on dashboard which I am guessing indicates normal pressure.

My engine management light and yellow warning triangle are on all the time along with a message saying check engine and stop start unavailable. But I would have though if it was losing pressure it would say stop engine.
 
Well guys Fiat have said it is the oil pump solenoid and pressure switch.

Total cost to replace both with oil and filter change will be £353.64 which I thought was pretty good for a main dealer!!

I have booked it in for Tuesday 8th September so I will report the results then.
 
Well guys Fiat have said it is the oil pump solenoid and pressure switch.

Total cost to replace both with oil and filter change will be £353.64 which I thought was pretty good for a main dealer!!

I have booked it in for Tuesday 8th September so I will report the results then.

Sounds promising..

Is this a 'guaranteed fix?'

No improvement..no charge
 
Sounds promising..

Is this a 'guaranteed fix?'

No improvement..no charge

That's a very good question and the answer is I am not sure but if they don't fix it I'll not be handing over any money without a fight.

I do suspect they are correct though as my stop start has been playing up prior to the EML coming on.
At times the engine would stop and then restart itself almost right away and other times it would start again after only about 20 seconds.
 
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