Technical Fiat Ducato - Power Loss when driving

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Technical Fiat Ducato - Power Loss when driving

Sue Wakefield

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Has anyone experienced power loss intermittently when driving? Can be driving along then suddenly there appears to be no power even with foot on accelerator to the floor. Power does eventually kick back in although sometimes there is quite a delay and we find ourselves having to pull over and leave it a few minutes before travelling on. Happens just driving along or when accelerating upon gear change.

The most annoying thing is it doesn't happen on all journeys. We were recently heading off for a few days but felt the need to turn back to take the vehicle to a garage - got home, emptied belongings then it never did it on the 15 mile trip to the garage!

Our local Fiat garage replaced the lower fuel pump. We collected the vehicle yesterday and it did it 5 times on the 15 mile journey home!

Fiat collected the vehicle today and it didn't reoccur on the journey back to the garage - so frustrating!

No warning lights appear on the instrument panel and no fault codes found upon diagnostic check.

This is a motorhome with a fiat Ducato engine. Purchased in August, 2015 plate with less than 3000 miles on the clock.

Any help would be much appreciated!

Thanks in advance.
 
Hi. So this is not a fault the system can self diagnose. That means to me that the Ecu thinks engine demand is good and the engine response to that demand is good. I guess that the potentiometer on your acceletor pedal or some associated wiring is dodgy. Others might add other sensors or wiring which might likewise offer a cloaked failure. The fuel pump replacement to me was a bad guess, must expect an error code with a fuel starvation.
Oh and look up a thread called money saving tip, explains how to check for loom damage (and while you are there water damage) under the passenger side head light near the main ecu and wiring connections.
 
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Thanks for the advice Andy Diver!

I will mention this to the dealer if they cannot diagnose, which I suspect they will not.

Will keep you posted.
 
Just to note that on the older (2002ish) Ducatos a problem with the throttle does show up in diagnostics and also lights the warning light.
 
Has anyone experienced power loss intermittently when driving? Can be driving along then suddenly there appears to be no power even with foot on accelerator to the floor. Power does eventually kick back in although sometimes there is quite a delay and we find ourselves having to pull over and leave it a few minutes before travelling on. Happens just driving along or when accelerating upon gear change.

The most annoying thing is it doesn't happen on all journeys. We were recently heading off for a few days but felt the need to turn back to take the vehicle to a garage - got home, emptied belongings then it never did it on the 15 mile trip to the garage!

Our local Fiat garage replaced the lower fuel pump. We collected the vehicle yesterday and it did it 5 times on the 15 mile journey home!

Fiat collected the vehicle today and it didn't reoccur on the journey back to the garage - so frustrating!

No warning lights appear on the instrument panel and no fault codes found upon diagnostic check.

This is a motorhome with a fiat Ducato engine. Purchased in August, 2015 plate with less than 3000 miles on the clock.

Any help would be much appreciated!

Thanks in advance.
Experienced the same thing once last month on our 8 month old motorhome just lost power then kicked in again as I was dropping down the gears wondering what was wrong , using the van again this weekend hope its ok . did you find out what it was?
 
I had this on a 2001 2.8, diagnosed immediately by auto electrician in Belgrade, they come across it often, bad connection(s) on the throttle position sensor circuit.
 
I'm afraid not. The garage had the motorhome for a further 2 weeks and couldnt get the fault to reoccur. We haven't used the motorhome over the last couple of months; plan to get back on the road next month. Please keep me posted as I will you.
 
Thanks! I'll mention this to the garage when it happens again cause I'm sure it will!
 
Hi,
I have experienced a very similar problem with my 2017 Fiat Euro 6 Pilote motorhome which would suddenly lose power without warning.

I took it to a Fiat commercial dealer who confirmed that the cause of the power loss was activation of the "brake throttle override (BTO)". BTO is a "safety feature", built into many modern engines, that will cut throttle power if the brake and throttle are pressed simultaneously. I have it on my Volkswagen Passat where normal function is restored immediately the foot is removed from the brake pedal. In short there is no problem with Volkswagen's implementation of the BTO.

The problem with the Fiat implementation is that power is not restored after the foot is taken off the brake pedal while the accelerator continues to be depressed. In fact, the only way to restore normal function is to take both feet away from the pedals for 3-4 seconds to reset the system.
I argue that this is counter-intuitive as most people will depress the accelerator if they suddenly lose all power. Furthermore, there is no reference to the brake throttle override or how to recover from the power loss in the vehicle manual.

Please note that I was not intentionally driving in a way that both feet were applied to the pedals simultaneously. I can only assume that one of the pedal sensors was overly sensitive or that I brushed the brake pedal with my right foot accidentally on occasions whilst changing gear. In any case, the sudden loss of power came as a shock and placed me into some very dangerous situations whilst I owned the vehicle.

I did write to Fiat about this issue but they were adamant that there was no problem with the vehicle and the problem was caused by my style of driving.

Readers of this reply can decide for themselves if they think it is safe to drive a vehicle that will suddenly lose all power if they inadvertently brush the brake pedal whilst changing gear. Furthermore, the power will not return if they continue to depress the throttle. My costly solution to this problem was to buy a Mercedes based motorhome which so far has functioned perfectly.
 
I suspect this is what occured to me once on a summer foreign holiday, a distinct loss of power just as I tried pulling into a busy roundabout (eek !). I think it was because I was wearing sandals which have wider soles than my normal footwear, and the left side of my right sandal caught against the edge of the brake pedal when pressing the throttle to accelerate. Once I had a chance to take my foot off the throttle for a second or two, normal power was restored when I reapplied it. Needless to say, I no longer wear sandals when driving!
 
I have had this problem on and off since owning the van, a 2014, 2.3 Multi Jet. It's driving me mad!

On acceleration or if the revs drop when I'm in a gear too high for the conditions, the van lurches and a warning comes up on the dashborad saying 'Hill Ascent Mode Not Available... See Handbook.' Sometimes it happens all day and then it drives perfectly normally for weeks on end. When the issue occurs I sometimes get a warning light and a message saying 'check engine.' If I stop, switch the engine off and wait a while the warning light goes out. At other times I have plumes of white smoke (particularly under load - accelerating or climbing hills). Once again, if I stop and turn the engine off, it clears itself. My local garage can find no fault codes on their diagnostic machine. Lately, and today for example, the van was driving perfectly normally (as long as I gently ease the accelerator on to nurse it up to speed and don't make sudden demands) then as I climbed a hill I lost all power. I even struggled to pass a cyclist. Again I get the warning, 'Check Engine.' Again I stop, switch off, wait and away I go again. The only thing now is... it's becoming more and more frequent.

All the mechanics I've spoken to are scratching their heads. I don't want to go down the road of refurbished injectors, turbo replacement, fuel pump replacement, this sensor, that sensor... I did that before with another van and it cost thousands. When the van is having a good day I cannot fault it, so I cannot see that replacing the above mentioned items will achieve very much apart from making the garage richer.
 
If you get a warning light or message then the system "knows" that something is wrong and an appropriate fault code will have been logged. Maybe your local garage's reader is of a type that can't "see" all the codes, and you need to try a Fiat professional dealer.
 
Might not be Fiat code but I'm looking at a p0235 code relating to Turbo activation which causes the power to be cut if Turbo is not activated by the actuator to meet the predetermined pressure required. Check the rubber hoses that feed actuator etc.
 
I suspect this is what occured to me once on a summer foreign holiday, a distinct loss of power just as I tried pulling into a busy roundabout (eek !). I think it was because I was wearing sandals which have wider soles than my normal footwear, and the left side of my right sandal caught against the edge of the brake pedal when pressing the throttle to accelerate. Once I had a chance to take my foot off the throttle for a second or two, normal power was restored when I reapplied it. Needless to say, I no longer wear sandals when driving!

I have the same footwear issues! On a 05 2.8 jtd. I now have a pair of narrow shoes in the cab for driving only, sandals being ditched whe we go out. However, no loss of power or fault codes, just combined brake and gas- not helpful in lower gears. Pedal bent away from body side by previous owner, so made worse. Can be scary finding vehicle accelerates when you think you're braking and brain takes a blink to catch up!
 
Has anyone experienced power loss intermittently when driving? Can be driving along then suddenly there appears to be no power even with foot on accelerator to the floor. Power does eventually kick back in although sometimes there is quite a delay and we find ourselves having to pull over and leave it a few minutes before travelling on. Happens just driving along or when accelerating upon gear change.

The most annoying thing is it doesn't happen on all journeys. We were recently heading off for a few days but felt the need to turn back to take the vehicle to a garage - got home, emptied belongings then it never did it on the 15 mile trip to the garage!

Our local Fiat garage replaced the lower fuel pump. We collected the vehicle yesterday and it did it 5 times on the 15 mile journey home!

Fiat collected the vehicle today and it didn't reoccur on the journey back to the garage - so frustrating!

No warning lights appear on the instrument panel and no fault codes found upon diagnostic check.

This is a motorhome with a fiat Ducato engine. Purchased in August, 2015 plate with less than 3000 miles on the clock.

Any help would be much appreciated!

Thanks in advance.

Hi Sue,
I have had the same issue previously. Check the connectors on the spark plugs, they are poor quality and often lead to limp mode stalls
 
We have recently experienced similar problems in our brand new Swift Select Fiat Ducato motorhome. On the first trip to collect it (about 200 mile trip) when nearly home, we lost power twice pulling away from roundabouts. Fiat then told us about the “safety feature” if you touch the brake and accelerator at the same time and said this would have been the problem. We don’t think we did but my husband has fairly big feet and the pedals are very close together, so we accepted the explanation. The next time we took it out was for a trip North (about 500 miles over 3 days), we lost power in the fast lane of the M25, again well into the journey home – VERY SCARY although we managed to coast to the slow lane without incident. We were aware of the brake issue and are positive we did not touch brake and accelerator together. Shortly before we got home we had a red warning light and transmission failure warning.
Fiat took the van and looked at the computer and like other complainants they say we must have touched brake and accelerator again, that this is a safety feature and they will do nothing.

So I would like to know what other people have done – I see several threads on different forums on this issue – it is affecting a lot of people but mainly motorhomes I think. Has the problem gone away for you ? Have you found a fix ? Have you just learnt to drive with it ?

Although I have seen a lot of posts on this issue I cannot believe that this problem can affect all Fiat Ducato vans without there being a single serious accident that would have created more noise – what we experienced was very dangerous and there are thousands of Fiat Ducatos on the road. So do we have a problem van (possibly a dodgy sensor but how can we get Fiat to believe us), are only certain vans affected (is it just automatic motorhomes ?) or is the problem genuinely very intermittent (both times it was raining could that be a factor ?).

We are not going to get Fiat to do anything at the moment unless we have a serious accident (and they may still say it is our fault), and we cannot afford to just ditch the van and buy another, so I would really appreciate other views as I am very nervous about driving our lovely new motorhome at the moment.
 
had it twice on my 2019 Ducato im sure its the throttle thingy (not a technical term ) it did it at busy traffic islands holding it on the footbrake and then quickly swapping to accelerater without using handbrake
 
Hi everyone,
interesting reading on this thread.

I've got a 2010 Swift Bolero MH on the Ducato 2.3 MJ engine and I returned from a 2,500 mile trip just before the lockdown.

On the trip I lost power rapidly when travelling at around 50/60mph on 4 occasions and was reduced to limping along at around 4mph with max throttle pedal.

It wouldn't have been too bad had the first time not been in a mountain tunnel with nowhere to pull over ... and the second time on a motorway near Pamplona where the police escorted me off at walking pace on the hard shoulder with one officer walking 100 yards behind me and a police car 100 yards behind him.

The good news is that on the way back two months later the two times it happened didn't cause any havoc with traffic, but it needs fixing

My foot was never near the brake pedal and the second is that the fault always cleared itself eventually... the longest time to get the revs back to normal was 20 minutes at the garage in Pamplona.

I kept pumping the throttle and eventually a couple of loud bangs and clouds of exhaust black smoke and off we went again ...we thought it was dodgy fuel.

It ran beautifully for hours between the 4 incidents on the journey.

My pal's OBD says it's a throttle link short circuit and EGR fault so I'm planning on stripping the front to access and taking both off for a good decoke after watching a couple of Youtube vids on it.

Any advice gratefully received please:) ps fault codes from memory 0402 0638
 
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0638 is the Throttle and it is very likely due to poor connection on the throttle body solenoid. I had a couple of years of intermittent failure, improved by cleaning the connections to the solenoid, then by replacing it. There are a couple of threads on this. I was ultimately able to buy an actuator of the original design and swap it in from underneath the van, however, needed dexterity and they since changed the design so hard to find the old, you are best replacing the whole body. You must check the state of the wiring all the way back to the Ecu first else you will waste your time and money. Almost certainly not the EGR by the way.
 
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