Technical Ducato 230 2.0 JTD Engine dies all the time

[jackwhoo]

Hi,

Just have to say wow that was fantastic trouble shooting

From what you have written I am sure you have a problem with the in tank pump and possibly it's gauze filter.

Thanks for the updates.

I'm looking forward to next update.

Best wishes
Jack

 

[grachal]

Thanks for your help guys! The new fuel pump majorly has fixed my issues. As I got the new sending unit, I was able to see that the pump already has been a aftermarked one with smaller outer diameter, thus the prefilter system wasn't able to work properly. When I bench tested the old pump it did not pump consistently. Most likely its internals are worn down due to the non filtered fuel entering it.

But now I have a new smaller issue. Sometimes when I shut the engine off, it continues to run for a few seconds, until the fuel pressure drops. This also drops a P0191 code then and on the next starting cycle the engine is in limp mode because the code is saved.

I can avoid this by stalling the engine instead of turning it off by key.

From my understanding the engine normally is shut off by the ecu not opening the injectors anymore. Or is there a Shut-Off valve somewhere?

 

[Communicator]

Thanks for your help guys! The new fuel pump majorly has fixed my issues. As I got the new sending unit, I was able to see that the pump already has been a aftermarked one with smaller outer diameter, thus the prefilter system wasn't able to work properly. When I bench tested the old pump it did not pump consistently. Most likely its internals are worn down due to the non filtered fuel entering it.

But now I have a new smaller issue. Sometimes when I shut the engine off, it continues to run for a few seconds, until the fuel pressure drops. This also drops a P0191 code then and on the next starting cycle the engine is in limp mode because the code is saved.

I can avoid this by stalling the engine instead of turning it off by key.

From my understanding the engine normally is shut off by the ecu not opening the injectors anymore. Or is there a Shut-Off valve somewhere?

That is my understanding for elecronically controlled engines generally. The existence of a Shut-Off valve would be news to me. This raises the question as to what the engine is running on after the key is turned off?

 

[jackwhoo]

Could you have an injector that's leaking fuel past nozzle and so causing engine to run on until rail pressure drops?

 

[grachal]

If it was one or more leaky injectors I think the engine would sputter and then come to a stop. But it keeps running smooth, then slowly dies off, until the rail pressure is gone. So it seems like the ecu just keeps firing?
I think this must be an electrical issue, maybe the ignition switch itself?

 

[Communicator]

I appreciate the logic of the smooth running of the engine weighing against a leaking injector. The ignition switch explanation is also problematic.

The 2.0jtd uses a Bosch 15C7 ECU, as does my 2.8jtd.

On both engines there is only one contact on the ignition switch that is used to control the engine. There are however several supplies to the ECU. Turning the key supplies 12V to pin 58 of connector A of the ECU. This initiates signals between the ECU and the key code receiver, to check for known key. If OK the ECU operates the Main Injection Relay, T9, and injection is allowed. The connection to A58 of the ECU is not shown on the eLearn Engine management diagram (E5050), you have to go to the Key Code drawing E7010 to find it.

I am wondering if on switching off the engine T9 is sometimes slow to release. This could be due to corrosion inside the engine bay fusebox allowing the relay to make a resistive earth through headlamps or other accessories. The other alternative would be a faulty relay with a worn or missing residual air gap pin. This would allow the relay to remain operated with no current through the coil. I have not read of this in a vehicle context, but I have encountered it in other disciplines.

So two possibilities, but both seem unlikely. I am always sceptical when relays are suspected without reason.

 

[grachal]

Thank you for the diagrams, for me they are a bit overwhelming tbh.
Today I noticed that I was able to pull the key from the ignition switch while the engine was running. Dont know if this always has been the case, or it just happened today. But I never saw a problem with the Code Light in the Dash, so I think there shouldnt have been problems?

I decided to take it all apart, but doing so I unfortunately messed up the mechanical side of the ignition switch.

Now I did a test (did this before I read your explanation, otherwise I would have known, it wont make a difference), where I fixed my key to the ring antenna/code reciever and started/stopped the engine solely by the electrical unit of the ignition switch.
But the same problem happens, when I turn it off, fuelpump shuts off, but engine keeps running until out of railpressure.

Where exactly in the engine bay is the relay T09 located, I want to check/replace it?

 

[Communicator]

Am I co

Thank you for the diagrams, for me they are a bit overwhelming tbh.
Today I noticed that I was able to pull the key from the ignition switch while the engine was running. Dont know if this always has been the case, or it just happened today. But I never saw a problem with the Code Light in the Dash, so I think there shouldnt have been problems?

I decided to take it all apart, but doing so I unfortunately messed up the mechanical side of the ignition switch.

Now I did a test (did this before I read your explanation, otherwise I would have known, it wont make a difference), where I fixed my key to the ring antenna/code reciever and started/stopped the engine solely by the electrical unit of the ignition switch.
But the same problem happens, when I turn it off, fuelpump shuts off, but engine keeps running until out of railpressure.

Where exactly in the engine bay is the relay T09 located, I want to check/replace it?

Sorry to learn about ignition switch, as it will be matched to those on doors.

Are you referring to the LP pump in the tank, as HP pump driven by engine?

The relay T09 is in the engine bay fusebox, B001. The engine bay fuseboxese have a similar layout for several Fiat vehicles. I am attaching my own diagram of the fusebox, specific to options fitted on my vehicle, but OK for locating T09. Please not that my diagram is inverted when compared with the fuse & relay location shown at the top LH section of diagram E5050 previously posted.

As I suggested previously, I am sceptical when relays are suspected, but they are easy to check by substitution.
I think unfortunately, that problems with the fusebox are more likely. This fusebox is a known source of problems in the Ducato, and other models, particularly if it has got wet.

If I think of any further possibilities, I will add them to this thread.

 

[grachal]

In my previous post I was referring to the LP pump…
I do not have such a fancy fusebox in my engine bay, see attached what I am equipped with
When I pull the marked relay, the LP pump won't run, so I suppose its the fuel pump relay/T10. Switched it with the other black relay to, it is the same part number. But its the same deal, Only LP pump and lights in the dash shut off when key off, injection keeps running until rail pressure drops enough.

 

[Communicator]

Sorry, I was so engrossed with the content, that I was missing the fact that the vehicle is an x230 model. You have clearly stated that in the thread title.

That does make it more difficult, as the wiring, changed with the introduction of the x244 model.
Unfortunately I have yet to discover published engine wiring diagrams for the x230.

Perhaps try swapping the red relay with a black one for testing only. The red relays are rated at 30A, while the black ones are only rated for 25A. Should not matter for a few operations.

Also look for any signs of corrosion around the relay connections.

 

[grachal]

Switching the red for a black relay did not change anything. Checked and cleaned all the relay wiring that was easily accesible. Also cleaned a big connector in the ECU area. Did not help.
I also discovered, that the engine stays sensitive to throttle input after switching the key off

 

[grachal]

Update:
I found a post from a guy in a Peugeot forum, stating that he has seen the same issue on multiple 2.0 HDI's. He wrote its the fuel pressure regulator, most likely dirty or defective.
I gave it a shot, and to my big surprise. He was right. The tiny fine metal filter on the tip of the FPR was completely full of very fine debris, almost not visible to the eye (surprised that the fuel filter doesn't sort this out).
Cleaned it with brake clean, reinstall and voila. Engine stops normal again.

The big Question now is why?? Sadly the guy did not write this. Very interesting. Maybe the FPR acts as a shutoff valve?

 

[Communicator]

Congratulations, it has taken 3 months, but perhaps now you have succeded. I admire you perseverance.

 

[grachal]

I want to get back to you with a very late reply. Reason being i wanted to make sure, that the Ducato truly works and I don't jump to conclusions. Past few weeks I dailyed the car and last week I did a 1200 km trip to Italy and back: Without any issues at all!

I very much appreciate the help of all of you. There were definitely moments when I thought about just giving up and scraping the van. Thanks to every one of you, I was able to get this great car to work properly.