Technical Multipla JTD stops While driving (injection alarm)

[RadioMultipla]

Hi

I have the following problem with a Fiat Multipla JTD diesel 105 from 2000
Sometimes the engine stops while driving. The engine will then not start anymore and the alarm light for the injection is on. After half an hour the engine starts again, but then the fire alarm light for the injection is stil on.
If you turn off the engine off again and start it again, the light is goes off.
The error occurs only occasionally. Sometimes 1x in 3 weeks. The error seems to occur more frequently when the engine is not heated and if the tank is less than half full.

who knows what cause this problem

 

[jayc50000]

First thing to try is change the fuel filter.
If you still get the problem it's 4 main causes are an injector letting go and returning to much fuel. Pressure regulator on the back of the fuel pump faulty. Mechanical valve in the fuel rail sticking and dumping fuel pressure or poor connection at the rail pressure sensor.
Have you had the fault codes read?
More than likely will have p0089 fuel pressure low.

 

[RadioMultipla]

Thanks for your comment.
Do you have an explanation why after an error there can not be started for 30 minutes and after a waiting time of 30 minutes the car does start and can drive normaly ?

I'm going to let the garege to read the fault codes again, but two months ago I was in the garage with the same error but then the car would not start. Not even the next day.
So the did a readout and replaced an injector.
But now they have no explanation why the error comes back sometimes and why you can drive 2 or 3 weeks without an error.


Greetings

 

[jayc50000]

Yeah fuel pressure related fault can be tricky. When fuel is hot it's thinner and and the seals in injection parts slightly expand when hot with makes it Easier for fuel to pass. When the engine is left for a bit things cool down and let you build pressure again. If it's an intermittent fault more than likely the pressure reg or rail pressure sensor/wiring

 

[RadioMultipla]

Ok. the problems are not yet solved. Sometimes I can drive two weeks without problems. (= 1000km). Last time I had car trouble I was able to start the car again when I pulled off the connector of the new fuel injector

Now the garage put the new injector to another cylinder.
He sat on cylinder 3 and is now on cylinder 2.
This as a test.
Today I had again car trouble and stopped along the highway.

After disconnecting the connector for cylinder 2 (new injector) the car still will not start.

After disconnecting connector for cylinder 3 the car starts though.
If you push the connector on the injector, the motor stops direct with a loud tick.

Conclusion is that it is not the new injector,
It must be something else, but what?

 

[RadioMultipla]

Yesterday, the car stopped again on the highway. After pulling plug on cylinder 3 I could drive home on 3 cylinders.
Tested this morning. I put back the connector on the injector 3 and the engine stopped.
I drove to the garage on 3 cylinders . Approx. 10 kilometer. So once again put on the injector connector, but now the engine runs well again.
when reading from the computer i get a 0191 rail presure low error.

The garage believed that the computer needs to be replaced and this will be very expensive.

Who has experience with this?

 

[Giedriusss]

fault say that problem with fuel pressure, so it could be a fuel pressure regulator or sensor, but not ECU(computer).

 

[MultiplaAbarth]

OK, just a longshot, crank sensor?, these can be intermittent, causing same symptoms, try changing this before any expensive stuff...
I had this on my old 105jtd, very inconvenient..
Ignore the fact this link is for puntos, read it its relevant...good luck.
https://www.fiatforum.com/punto-mk2-2b-guides/147923-fiat-jtd-crank-rpm-sensor-removal-replacement.html