Have you used MES - or similar to get live data while it's in the "cutting-out" zone,
may just highlight what's changing at these temps..,
sounds like you've checked over ALL the basics,
charlie
Technical Ducato Motorhome cutting out
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Technical Ducato Motorhome cutting out
Have you used MES - or similar to get live data while it's in the "cutting-out" zone,
may just highlight what's changing at these temps..,
sounds like you've checked over ALL the basics,
charlie
Used FiatECSScan Interestingly sometimes the pressure is significntly higher than the desired preassure and other times it's signifficantly lower. From the way that the van start to feen a bit sluggish before cutting out, I suspect it's low preasure causing the P0191 fault however the High Pressure side seems to have passed tests fine, though as it only cuts out on hot days after the fuel has had a cance to warm up they may not have reached those conditions when testing the HP Pump?
could be worth taking live data with FES when it's buggering about then..,
at least you'll KNOW if it's low pressure at that time,
charlie
at least you'll KNOW if it's low pressure at that time,
charlie
Fuel tank breather sounds likely!
Changed the filter lately?
Inspect all wires for heat damage, breaking down when hot?
Wash the rad out &/or drain & flush cooling system?
Just a few ideas from my experience as a bus mechanic
Changed the filter lately?
Inspect all wires for heat damage, breaking down when hot?
Wash the rad out &/or drain & flush cooling system?
Just a few ideas from my experience as a bus mechanic
Krosus
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Well you asked for obscure but this is the story.
I had this problem in the past, it happened right after servicing. The agent had fitted the wrong air filter and the engine cut out. This was a petrol based unit and as the air supply was insufficient the van just died when it reached operating temp. It took them a while to diagnose but they got there in the end. I suppose this can affect diesels the same way.
Best of luck
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I had this problem in the past, it happened right after servicing. The agent had fitted the wrong air filter and the engine cut out. This was a petrol based unit and as the air supply was insufficient the van just died when it reached operating temp. It took them a while to diagnose but they got there in the end. I suppose this can affect diesels the same way.
Best of luck
Sent from my iPhone using FIAT Forum
OK, still getting the same problem but this time managed to get it to cut out with the laptop attached logging data. It appears that it will cut out if the Fuel pressure fulls to more than 20% below the Desired pressure.
Engine speed Fuel pressure "Desired
fuel pressure"
3394 1230.4 1347.8
3440 1250.6 1348.8
3012 540.9 597.2
2640 830.6 950.8
2663 968.2 1270.4 Engine Cut out
2688 132 100
One thing I did notice was that the 3rd Piston deactivation solenoid was active all the time which I presume means the pump is working on 2 of 3 pistons. If the fuel pressure is too low shouldnt this close/deactivate when demand is high?
Engine speed Fuel pressure "Desired
fuel pressure"
3394 1230.4 1347.8
3440 1250.6 1348.8
3012 540.9 597.2
2640 830.6 950.8
2663 968.2 1270.4 Engine Cut out
2688 132 100
One thing I did notice was that the 3rd Piston deactivation solenoid was active all the time which I presume means the pump is working on 2 of 3 pistons. If the fuel pressure is too low shouldnt this close/deactivate when demand is high?
I thought you said the solenoid was on all the time earlier. How does it run with the solenoid disconnected?
It is called the 3rd piston deactivation solenoid. When powered it deactivates the 3rd piston on the HP pump reducing the fuel pressure. Graphing the ECU data shows that it is rareley powered off and so the 3rd piston is deactivated most of the time, which may be why it's strugling to reach the desired fuel pressure.
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Sounds like 3rd piston may be the culprit if prssure is too low, but what causes it to activate most of the time? Here's another thought....
I have an 05 Renault espace, 2.2Dci common rail, and that has a fuel temp sensor somewhere in the fuel filter assembly. Has the Duc got a fuel temp probe too? If so, maybe thats worth a look? As for the heat gun thing, would a hair dryer do?- less chance of damage with that (unless SHE catches you using it on a smelly diesel, lol).
With the Ren, only mfrs. diagnostix will pick that up, no over the counter stuff will.
Good hunting!
I have an 05 Renault espace, 2.2Dci common rail, and that has a fuel temp sensor somewhere in the fuel filter assembly. Has the Duc got a fuel temp probe too? If so, maybe thats worth a look? As for the heat gun thing, would a hair dryer do?- less chance of damage with that (unless SHE catches you using it on a smelly diesel, lol).
With the Ren, only mfrs. diagnostix will pick that up, no over the counter stuff will.
Good hunting!
Good idea. The fuel temp sensor is integrated with the pressure sensor, which I have replaced. Having mapped the Temp on both sensors they seem to be reporting the same temp range, so figured it's OK, though as the fuel temp rarely gets above 38c I am a liitle surprised because under high pressure I would expect it to be much higher (based on 3rd piston deact not cutting in until 103C). Back to the drawing board this weekend to do more testing.OK gave the van a good run to a Festival last week and have a better understanding of what is happening. (1) even when cold there is a slight hesitation when reving between 2700 and 3000 rpm. (2) when warm will not take any strain (i.e. up hill etc) between 2700 rpm and 3000 rpm, in this rev range under any strain it will cut out with P0191 error and will re-start after a minute or so. (3) If I rev higher in low gears so that it is above 3000 rpm when I change to the next gear, then it seems to pull OK without cutting out. (4) every time it cuts out the desired fuel pressure is around 1000 bar and the actual is around 17% less. (5) have mapped a number of runs with MultiECUscan and the pump regularly reaches >1300 Bar no problem. (6) Only noticable thing from the recording is that the 3rd piston deactivation solenoid is almost always active (so pump only running on 2 pistons 95% + of the time). Have tried running with the solenoid disconnected but this throws a differnt error that also causes the engine to stop (due to an over pressure at low revs). So has anyone any suggestions as to what could cause this at a fairly narrow (2700 to 3000 rpm) rev range and to run fine otherwise?
Its easy for the pump to produce 1300 bar when the injected quatity is low. From memory of the ecu map at that rev range the ecu is injecting up to 78mm3 per stroke under full load, at higher revs the ecu reduces the injected quantity so the pump can probably maintain pressure. The fact that its failing to maintain pressure points to lift pump, filter, pump, injectors. My moneys still on an injector how did you do the leakoff test, did you rev the engine etc.
Ok, finally got round to doing another leak-off test. As I can pinpoint the problem to around 2700 RPM (that's where it cuts out when under strain and it runs rough around 2700 rpm in neutral as well) I ran the leak-off for 5 mins and held the revs at 2700 3 times for about 1 minute. Results Injector 1 = 65ml , 2=58.5ml, 3 = 59ml, 4 = 60ml.
Injector 1 definitely leaks off ~5ml more than 2,3,and 4 but is this within expected tolerance? or have I finally found the problem? Thoughts please.
Injector 1 definitely leaks off ~5ml more than 2,3,and 4 but is this within expected tolerance? or have I finally found the problem? Thoughts please.
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Would injector 1 excess leak off not just cause lower power... or does that fault command an ecu shutdown routine as a factory set parameter? I know an new injector ain't cheap, (what about a recon one?) but if desperation takes over.......?
What a load of stick you're having, sorry mate, hope it gets sorted. Tho' it does look like something doesn't like a combo of temp/load/rpm. My money is on electronix, but what? I don't know.
What a load of stick you're having, sorry mate, hope it gets sorted. Tho' it does look like something doesn't like a combo of temp/load/rpm. My money is on electronix, but what? I don't know.
I would say thats within tolerance, if its running rough consistently at 2700 in neutral you may be able to see something happening in live data, obd is too slow for transient events though so you might need to scope the sensors.