Fiat Ducato losing power when accelerating

UFO

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My 2009 Adria Twin Fiat Ducato 100 Multijet/2.2 HDi (Ford Puma engine) developed a problem on the last trip.

I first noticed it a couple of days ago. When accelerating in any gear the engine would sometimes lose power and stop accelerating. Sometimes it would clear and the acceleration would pick up. Other times I would change gear and the acceleration would be ok. There was never a problem when cruising at any speed.

Coming home today on the A303 single-carriageway section traffic was slow (there was broken down vehicle further along) suddenly I could not do more than 10 mph in 2nd gear. The signs said there was a duel-carriageway section ahead and parking 2 miles ahead. I continued, slowly, just before the parking area the acceleration started to pick up and I got into 3rd, although the acceleration was lumpy. Stopped in the layby turned the engine off, when started the engine revved freely to high revs. Continued on our journey and got home ok, with only the occasional slight loss in acceleration.

No dashboard lights at any time.

Filled with fuel and added Redex Diesel System Cleaner at the start of the journey and filled again when tank was half full, at which time the problem was already present.

Any ideas before I hand it over to the mechanic? It seems that the engine is being starved of something – fuel or water, but why only occasionally?

thank you
 
Check the air filter for mice.
No mice and the filter looks new - as it should do as the van had a full service at the beginning of April. I did find the seal from the top cap scrunched up in the bottom but I am not sure whether this would have caused the problem as there should have been no interruption to the air supply.

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No mice and the filter looks new - as it should do as the van had a full service at the beginning of April. I did find the seal from the top cap scrunched up in the bottom but I am not sure whether this would have caused the problem as there should have been no interruption to the air supply.
With debris from a filter change in the bottom of filter casing I would check the 'U bend' to ensure there is no other debris which is occasionally drawn up to the 'air mass sensor', in my case it was a dead mouse, and caused very similar symptoms to yours.
 
So Hard to tell without putting a OBD2 diagnostic, so many things could cause this issue.
mine was throttle body.
 
So Hard to tell without putting a OBD2 diagnostic, so many things could cause this issue.
mine was throttle body.
Even with a diagnostic tool it's not always easy, my van threw several errors, Fiat (un)Professional started on the "replace this, replace that" approach, so I took it away from them, and took it to Nick Fisher of EuroTrucks, at the time a large Fiat rental company with their own workshops. Even he struggled to find the problem, in the end he sat in the passenger seat with a full diagnostic suite plugged in and the van was driven for many miles until an error occurred and he could see in real time what the sensors where showing, from that he decided something was upstream of the AMS, stripping the pipes and out dropped a dead mouse.
Mice getting in the filter of x250/290's motorhomes is now recognised as fairly common if they are laid up for a few weeks at a time.
 
Even with a diagnostic tool it's not always easy, my van threw several errors, Fiat (un)Professional started on the "replace this, replace that" approach, so I took it away from them, and took it to Nick Fisher of EuroTrucks, at the time a large Fiat rental company with their own workshops. Even he struggled to find the problem, in the end he sat in the passenger seat with a full diagnostic suite plugged in and the van was driven for many miles until an error occurred and he could see in real time what the sensors where showing, from that he decided something was upstream of the AMS, stripping the pipes and out dropped a dead mouse.
Mice getting in the filter of x250/290's motorhomes is now recognised as fairly common if they are laid up for a few weeks at a time.
But always a good starting point OBD2. So where does a mouse get in, does it gnaw through the air hose or filter housing??
 
Following on from RichardHelen262 says, it doesn't do any harm, once in a while, to give the vehicle a blast up the motorway in a lower gear and give it a few minutes of high revs.
As my mechanic says "blast the crap out of it and it'll be lighter on its feet".
It certainly worked wonders on my old Saab after I'd been driving it like a nun. thinking it was doing it some good. It wasn't!
 
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Following on from RichardHelen262 says, it doesn't do any harm, once in a while, to give the vehicle a blast up the motorway in a lower gear and give it a few minutes of high revs.
As my mechanic says "blast the crap out of it and it'll be lighter on its feet".
It certainly worked wonders on my old Saab after I'd been driving it like a nun. thinking it was doing it some good. I wasn't!
It also gets the oil up to temp letting the deturgents clean the inside of the engine, a good blast no and again is best as you say.
 
But always a good starting point OBD2. So where does a mouse get in, does it gnaw through the air hose or filter housing??
Fiat kindly built the x250/290 as a mouse play house, the inlet is built into the cross beam that bonnet closes onto, any mouse 'exploring' a van will think it's got a ready made house with easy access, the answer is to fit wire mesh across the opening.
 
Fiat kindly built the x250/290 as a mouse play house, the inlet is built into the cross beam that bonnet closes onto, any mouse 'exploring' a van will think it's got a ready made house with easy access, the answer is to fit wire mesh across the opening.

This pipe had fallen off the box (the opening facing the camera top of the photo) but I thought that this was just for the cab heater. Has this got anything to do with the engine air filter? Pipe looks like a drain for the box.

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This pipe had fallen off the box (the opening facing the camera top of the photo) but I thought that this was just for the cab heater. Has this got anything to do with the engine air filter? Pipe looks like a drain for the box.
That looks like the scuttle drain, or could be for the heater inlet.
 
Nor had that issue but ours even on a warm day, first start the engine has no power it just coughs and almost dies, but once up to temp it's fine. And okay all day.
 
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