The title alone would have caused some people here to look twice, as I've read that at least one of you thinks that 1997 2.5 TDi's don't have an ECU. Mine has. I've seen it, and it appears to be causing problems.

Intermittent power loss, or stuttering, is perhaps the best way to describe it, a problem not unknown in the wacky world of ECU's. The problem comes and goes, and appears to be caused or worsened by vibration.

Over the years, I've taken the vehicle (a Hymer motorhome built on a 1997 8140.47R Ducato) to a number of mechanics, including a Fiat main agent in France, but no-one to date has found the root cause. I booked the van into the Fiat agent for a diagnostic test, but when I drove it in and one guy opened the bonnet, there was a stampede of mechanics all wanting to look in the engine bay. They'd never seen an arrangement like it. Although there _is_ an ECU, it only takes care of rudimentary duties as the fuel pump is of the old-fashioned sort that meters diesel to each cylinder. Although they looked for a diagnostic port, they couldn't find one.

Over the years, there have been a number of theories expounded, including fuel lines letting in air, the fuel filter mesh being too fine, the MAF sensor needing to be replaced, the fuel pump solenoid cable being suspect, and so on. I've had work done on a number of occasions, but nothing has worked to date.

One of my favourite theories (I've had a few) has been a loose connection, probably to a sensor. But no amount of wire-wiggling or connector-tapping has produced so much as a hint of a stutter. Admittedly these test have been carried out with the vehicle stationary and ticking over - I've yet to find a volunteer willing to stand on the bumper while I'm driving.

This year I contacted a number of independent ECU analysts, but none has my particular ECU model number (Bosch 0281 001 224) listed in their databases. I thought it possible that the motorhome builders might have fitted a custom ECU, so I contacted Hymer. But they affirmed that the ECU fitted definitely came from Fiat. So can I ask anyone here who happens to have a similar van whether they have the same ECU.

One of these ECU specialists declared that there _is_ a diagnostic port on my vehicle. He said it was a 2-pin port and situated under the bonnet near the battery. I thought it unlikely (data comms normally needs more wires after all), but lo and behold when I looked this morning, I found a strange object. Oblong, mounted on the bulkhead, pointing upwards, and with a rubber cap, what I saw has 3 wires connecting it. When I removed said cap, I saw a circular white plastic moulding with what appears to be 2 or 3 connectors recessed into it. It may well be a socket of some description, but it's not of a type I've ever seen before.



As you can see from the pic, I've held a mirror up against it so the top can be seen more clearly. Can anyone here confirm that this _is_ a diagnostic port, and if so, what sort of plug it takes.

If it isn't a port, WTH is it??

This afternoon I talked with a technician in Guest Trucks (the Fiat agent in Wolverhampton), and according to him the ECU doesn't control any engine function (he thought) other than opening and shutting the EGR valve (maybe, possibly, it's hard to say without seeing the vehicle). I asked about the diagnostic port, and he said it was probably an older type of connector. I asked what the name for it was, and he said he didn't know. I asked whether I could bring the vehicle in for a diagnostic test, and he said it was doubtful whether they'd be able to connect it up to their equipment. He informed me that his company send all their 'computers' back to Fiat on a regular basis, so they simply cannot connect to older vehicles. I asked whether he was saying in effect that the vehicle was unrepairable, and he promptly denied this, saying that I might well be able to get it seen to elsewhere.

But not, it appears, by the Fiat main agent in Wolverhampton!

So my third question (for now) is can anyone here confirm that the 1997 engine does in fact have an EGR valve. If so, it seems these little beasties can get clogged, remain open when they shouldn't, and generally mess up the engine's performance.

That's it for now I think. Thanks for reading, and even more thanks if you have any information to impart.

In 1997 its probably got an old msa11 ecu, I doubt it has an air mass sensor you can check the intake hose, so it would be calculating the fueling from temperature and crank sensors. If its not a simple wiring issue I'd be thinking the crank sensor. Is there a rubber hose going into the ecu? That would be barometric sensor check for perishing, common for these to leak in other vehicles. Take out the crank sensor and make sure its clean.

Did you check in around the fuel filter for a 3 pin connector 2-pins wired. Kline on the other msa11 ecus I know is somewhere around pin 5-10 I think so if you can find the connector by tracing those you may be able to read some codes as a 2.4 marea which would be similar ecu.

egg is 1 in the diagram:

That should say egr instead of egg,

I checked the marea diagram and its pin27 is the diagnostic k-line the colour is white/blue which is same as later ducato models:

Click to enlarge:


You can get 3-pin to obd adapters on ebay

Forgive me - this is going to be terse. I just spent an hour typing a detailed reply, and it got lost.

First of all, thanks for replying!

Where is crank sensor please? Not near top of my engine, I think. Pics of other engines show it mounted outside near cambelt.

Only socket near fuel filter is 2 pin connected to what I assume is fuel sensor screwed into filter body. I assume you don't mean this.

Ebay traders I've contacted for 3 pin to ODB adaptor cable say it won't connect with my ECU, although why is not apparent. I assume this must be a software issue. Assuming I actually find the 3 pin diagnostic socket, I thought to get a 3pin to ODB cable, an ODB to USB, and then run MultiECUScan on a laptop. Seems that won't work, according to some.

No rubber hose going into ECU. I've cleaned EGR valve and several Junior Power Timer connectors though - thanks for tip.

If the problem is down to an intermittent connection, would that necessarily show itself with the vehicle stationary and idling while I shake various wires and connectors? IOW is there something about driving the vehicle that can't be simulated?

What is an MSA11 ECU please? Does the term refer to a type or family of controller? Maybe it's the O/S or software run on them??

Again, thanks.

An update to the great connectivity question is that checking here ...

http://www.idiagnostics.co.uk/

... for a Ducato 230 2.5TDS, it seems only the Bosch ABS 5.3 system is covered. IOW all I can do is check the braking system. I admit I'm a bit green when it comes to engine control, but is this definitive information do you think? Is it worth investing (what??) 20 to 50 quid in gear that might be wasted? I'll give it a go if people think there's a good chance of success, but not if there's no chance.

MSA11 is a family of bosch ecus, crank sensor measures the rotation of the crank shaft it gets its signal from the flywheel so just follow around the bellousing and you'll find it if it has one.

[edit]
Just did a quick google and according to ecuelectronics.co.uk it is indeed an mas11 ecu - msa11 7.9 to be exact.

http://www.ecuelectronics.co.uk/pro...1001224--46-464-873-46464873-MSA11%2d7.9.html

Cable is only £10 you'd spend that on diesel driving to the garage, no point in buying the cable unti you've located a socket though did you look for connectors, wire colours like I showed you up around the filter area. or in the that side of the enginebay.

This is the manual for a similar injection system, the ducato one is probably less complete in terms of sensors though and uses a simpler map.

http://www.citrotech.se/data/pdf/xm/manual/2_XM.146-00-9.pdf

The old iveco scanner could porbably read it, it might be worth asking iveco garages.

Have located what I assume is the diagnostic socket. It was lurking under the nearside seat right next to the ECU. I'd removed the nuts holding the ECU in place, but only withdrawn it from under the seat enough to look at the connector and serial number. A further tug revealed the socket. It is a 3 pinner, but there are 3 wires going to it, and not 2. Whether or not they're all connected is another matter. Have ordered a 3 pin to ODB adaptor cable, and am now wondering which ODB to USB cable I should get. This ...

http://www.ebay.co.uk/itm/MultiECUS...iagnostic_Tools_Equipment&hash=item3f2891f755

... or this ...

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=360615491798&fromMakeTrack=true

... or maybe I should just buy the parts and make up a cable myself. It seems a lot of the time, people end up having to modify what they've bought in order to get things to talk with one another.

Have now located and cleaned the crank sensor. No change. Then tapped both it and the connector with a screwdriver while engine running at fast idle. No joy.

The question occurs, what exactly is the ECU doing when there's an old-fashioned diesel pump? It can't be anything to do with timing, can it? The only thing left is mixture control, or controlling the amount of fuel that gets added to the air. So how does the ECU control the fuel supply? It can't be a simple solenoid controlled valve - that would solely be on/off. Unless it is such a valve, and the ECU merely turns it on and off at high speed to meet demand. If so, would this be the main solenoid valve on the pump? I had assumed this was solely used to turn fuel off when stopping the engine, but maybe it has more to do.

hymerhobo said:

Have now located and cleaned the crank sensor. No change. Then tapped both it and the connector with a screwdriver while engine running at fast idle. No joy.

The question occurs, what exactly is the ECU doing when there's an old-fashioned diesel pump? It can't be anything to do with timing, can it? The only thing left is mixture control, or controlling the amount of fuel that gets added to the air. So how does the ECU control the fuel supply? It can't be a simple solenoid controlled valve - that would solely be on/off. Unless it is such a valve, and the ECU merely turns it on and off at high speed to meet demand. If so, would this be the main solenoid valve on the pump? I had assumed this was solely used to turn fuel off when stopping the engine, but maybe it has more to do.

Click to expand...

Its all explained in the document I linked to. If you an't fathom the electronics or find someone that can. One possibility is to replace the whole head of the pump with the mechanical head from another pump, its common to do this with TDI engine swaps.

Hi guys,
It’s ref this engine.
8140.47R 2.5tdi 1998
I’m after a modified fuel pin.
07917335330

I have a 1997 weinsberg with the same engine. It developed a very similar fault over 12 months ago and for love nor money can I get it fixed. I've had two cables made up but nobody could talk to the ecu. My 3 pin cable is also inside cab next to ecu.
Only difference on fault is mine has a square red light on dashboard which came on when fault started.
The error code is in manual which says defect in fuel injection system.
So many mechanics have told me it won't be injectors so they haven't been done. Turbo has been off and so I'm told its fine.
I'm really struggling to find fault.
Any ideas or help woukd be greatly appreciated.
I have many pictures and much more info to share but in a nut shell that's where I'm at.
Vehicle drives like it has no turbo however it does boast fir 1 to 2 seconds the red light comes on and it dies off. You can feel the boast before it gets turned off by presumably the ecu.
Many thanks
Peter