Technical ECU location, loss of power, acceleration problems 2014 2.3 multijet

[CEDD]

Hi I am new to the Fiat Forum. I have been having difficulties with My Fiat Ducato 35 LWB 2.3 multijet 2014 (old style)

I am unable to find information about where the ECU is located? I have found the airbag ECU in the footwell of the cabin.

Vehicle Reg: LF14 WXB

Fiat Ducato 35 2.3 multijet LWB 2014

I have had all sorts of performance issues and symptoms over the least 6 months. The van has been into my local
garage (who maintain a fleet of Ducato vans for a local firm) a number of times but they have been unable to find
a cause / solution.

The milage reading on the dash is constantly flashing. Glow plug warning light is showing fairly regularly. Showing open circuit.

Initially, the van presented with a very repeatable problem. When the revs were around 1900 rpm and I accelerated
the engine would 'kick' then ESC light, ASR light would come on. Check engine error message. Sometimes the engine
would stall altogether, sometimes a loss of power, sometimes a plume of white smoke from the exhaust. Generally,
pulling over, stopping the engine, then restarting after a few seconds would 'reset' the problem for a while.

No fault codes were recorded.

The fault started to happen more often, then became a regular thing. I had to adapt my driving to avoid that rev range
1900 - 2000 revs. Because it was in this range I wondered if there was a turbo related issue?

The garage replaced the fuel pressure sensor & crank shaft sensor. No change.

They stated there could be a wiring problem causing the symptoms. Or fuel injectors.

On the next visit, they cleaned out throttle body and EGR feed pipe - both heavily sooted up. They also stated there
could be a wiring problem causing the symptoms.

The symptoms changed dramatically. there was white smoke coming out of the exhaust almost constantly, a big plume of it
- a red arrows sort of thing.

The only time it stopped was when the engine went into fault mode. This was a complete reverse of previous symptoms,
where the engine would go into fault and then white smoke appeared.

Then on about the 5th journey, everything seemed fine with the engine. I could drive the van normally without having to
compensate to avoid the engine going into fault mode. The engine also seemed more responsive. At this time, I wasn't
getting my hopes up.

But this continued (mostly) for the next 10 days or so. The engine went into fault 2 or 3 times when heavily loaded and
going up steep hills. I noticed a small amount of black smoke from the exhaust when accelerating at these times. But on the
whole performing much better 95% improved.

I started to wonder if cleaning the pipes out had shifted something, and the first few days after I picked the van up, the last residues
had been working through the system.

Then about 5 days ago, the problem with the plumes of white smoke started again.

It has been back to the garage. A number of fault codes have come up and the garage are suggesting

Replacing the glow plus, replacing cam shaft sensor, replacing exhaust temperature sensor - coming from Italy.

I asked whether the ECU could be faulty - rather than lots of different parts. They said it was quite an involved process
and a 10 day turn around to get ECU checked.

This is where I am at the moment and I'm wondering how to proceed. Any suggestion greatly appreciated.

Many Thanks
Craig

 

[LandyAndy]

I would try a road test with the EGR vacuum solenoid disconnected and see what it drives like. This will bring a dash warning light on which will need a gadget to clear.
With the previous work did they see if EGR worked, or was stuck open or closed.

I think they just want to throw parts at it as they don’t know.

 

[Anthony489]

Hi Craig

To answer your direct question, the ECU is inside the engine compartment, on the passenger side (RHD) and behind the fuse box. It is rather hidden, but look for a metal box the size of a paperback book with a couple of multiway connectors on top. The ECU is programmed to the specific vehicle, but normally a specialist refurbisher will be able to download the relevant information and use it to reprogram after any repairs.

However, although it is possible that you indeed have an ECU problem, I think it more likely that it is another component so you might want to eliminate those first. White smoke is unburnt fuel, and can be an indication that at least one injector is providing too much fuel for the available oxygen. However, intermittency (plus odd warning lights) is more often associated with electrical issues, e.g. a chafed wiring loom that is occasionally shorting. The favourite area for this is near the ECU, where a loom is strapped to a metal tube and can rub. It's best to remove the passenger side headlamp to get a better look at what's going on.

As LandyAndy says, if you pull off the thin vacuum hose between the EGR solenoid (central, under scuttle) and the EGR, the EGR will default to its closed position assuming it isn't physically jammed open. This can be a useful diagnostic if it is the EGR system that's playing up. An EGR valve that is open when it shouldn't be will feed the engine with excessive amounts of oxygen depleted gas, to the detriment of combustion.

Although intermittent issues like this are difficult to track down, I can't help feeling that your present garage are now changing things more in hope than as a result of logical thinking. If you are getting restricted power mode there will always be associated stored fault codes which will be a guide (and no more than that) to the problem area. This might be a candidate for a good Fiat garage, as although their labour rates may be more it may take them less time to pinpoint the problem.

Finally, although your vehicle is relatively new, there is always a small possibility that the engine to body earth strap is failing. I suggest this is checked, to eliminate it as a cause.