Technical Fiat ducato code p0016

[Seanwinder22]

Hello everyone I’m Sean new here and very new to the motorhome life
I have hired a few over the years until saved up
Here I am learning as we go
Anyway I bought a 59 plate 3.0 comformatic fiat ducato bessacar e660 78000 miles full service history first had issues with the gear box jumping from auto to manual that’s now fixed
Now warm start issues
First start is fine and drives no issues
But turn off then try it will not start or if it does will stall
Anyway we got to got to the site as planned no codes or issues
Time for home days later this is when it started
Started van as normal parked up turned off to hand in keys that’s when would not start on third attemp it throws code po340 camshaft sensor bank 1
Rac recovery unplugged cam sensor which did get us home until got to a garage
Now is when issues got interesting lol
So garage diagnostics said cam sensor & crank sensor so got changed
At this point Another code came up p0016 correlation which is crank timing apparently
A few issues can cause this bad oil or not services enough
Crank sensor or wiring even vvt or solenoid valves
Then these codes
(P2243 - Lambda sensor electrical diagnosis
P0053 - LambNa sensor resistance
P0340 - Phase sensor
P250A - Engine oil level sensor
A service and oil change cleared p250A
Codes are now p2243 and p0016
Continuity tests done sensors changed twice new oil filters
May I add also on the full history I found receipts of timing chain replaced at 73000 miles the van is now at 78000 this work was carried out 9 months ago that’s the only information I have
I’m told my issues due to all other checks done leaves bad timing or not done correct the first time
I’m lost and stuck on information being a private sale and these codes came on after sale
I’m honestly so stressed out and stuck
Stuck on finding a good mechanic to help me in South Yorkshire 2 garages lead me in for a fix and did all work mentioned but no fix
The last it just left said only thing now buddy is timing chain 8 hour job 900 quid ????? I fear now what if I pay this and it’s not the issue any help would be great I’m honestly really worried the van wasn’t cheap

 

[Anthony489]

Hi Sean

Some background information. These engines have a crankshaft position sensor ("rpm sensor") so that the ECU "knows" when a cylinder needs to have fuel injected. They also have a camshaft position sensor so that the ECU knows which cylinder is which. Once the engine is up and running, loss of the camshaft sensor signal won't stop the engine as it can carry on working fine with only the crank signal, albeit it will throw an error code. However, starting is only possible with both sensors working. These sensors have been known to have temperature related failure, i.e. they fail when hot and come good again when cold.

If the sensors are OK and fitted properly, there is the possibility of a wiring loom fault. A careful visual inspection can sometimes show if a loom has been chafing against something, a situation that can occur under the passenger side headlamp for example. A properly equipped workshop will be able to put an oscilloscope on these sensor outputs at both the sensor and ECU ends of the wiring and look at the waveforms when cranking. This is a much more reliable test than simply "buzzing through" the wires.

When you get multiple seemingly unrelated fault codes, it's unlikely that you genuinely have multiple faults. Far more likely is that there is a common cause. This might be in an early stages of the 12 volt power wiring, i.e. before it has been split down via fuses to multiple feeds. Alternatively it could be part of the "earth return" wiring. I suggest you get the battery connections and the heavy current terminals checked out, plus the engine to body earth strap (ideally replace it plus clean the nut and bolt fixings). This may not cure your troubles but is a basic first step to eliminate them as possible causes.

If the engine runs at least some of the time then I think it's rather unlikely to be the timing chain mistimed. The chains rely on sprockets (think bicycle chain) and there are fewer coarser teeth than with toothed rubber belts - see picture attached. If a chain was fitted with a sprocket one tooth out that would be something like 14 crank degrees in error. Such a big error ought to be immeditely noticable visually to whoever was doing the job (the arrow marks would not align properly), and the engine performance would be terrible. Also, chains don't just slip teeth unless they are worn out beyond redemption.

What you need (along with everyone else) is someone who can apply a bit of logic to this problem rather than just replacing parts and crossing fingers. I wish you well in finding this "someone".

 

[Anthony489]

Just found some more data on the cam and crank sensors, see pics.

 

[Anthony489]

And finally:

Here is a diagram I drew to show the time relationship between the crankshaft position signal (which has a "glitch" twice per crank revolution) and the camshaft position sensor signal (which has a clear pulse once every two crank revolutions). The signals are diagrammatic, but you get the idea. The ECU can determine when it is Cylinder 1 which is at top dead centre on the compresssion stroke, and then just counts 1,3,4,2,1,3,4,2 etc. to determine the rest of the sequence. The fuel injection is timed according to the crank signal, as this is the more accurately timed.

The ECU can also check that the timing of the cam signal is not too early or late compared to the crank signal, and will throw an "incorrect relationship" P0016 error code if it deems it to be too far off. I don't know what the acceptable range is, but I would guess at something like plus or minus 5 crank degrees. If the chain was fitted a tooth out on the crank or intake cam sprocket then (assuming the engine started) the 14 degree crank error would immediately trigger this code. If the ECU can't find a satisfactory cam signal at all it will throw a P0340 or P0341 error code, it MAY also throw P0016 because if there is no signal then there is by definition an "incorrect relationship".

Whilst walking the dog I got to wondering. These chains don't wear out as a function of time, so don't need changing every 5 years like a belt. They are a mature and reliable technology which is supposed to last for a very long mileage, and some people have reported over 200,000 miles. Eventually the day will come when the chain has worn and stretched enough to trigger a P0016. But why has the previous owner gone to all the trouble and expense of having it changed so early at only 78000 miles ? Is there some problem with the sensors, sensor wiring, sensor position/alignment, chain sprockets, sprocket keyways, chain tensioner, chain tensioner oil supply or whatever which has caused a sensor alignment warning, and the chain has been changed to no avail in an attempt to fix it ? Is it possible that the engine is operating almost at the limit of acceptable error (say +/- 4 degrees), so it doesn't take much extra timing shift to push it "over the edge" ? I fear that just changing the chain again will get you no further, and a more detailed investigation is needed by someone with the right skills.

 

[Seanwinder22]

thanks for the reply appreciate it
I have had a auto electrian on the van who carried out the continuity tests to the cam and crank and Ecu says all fine
It was with them 2 days he phoned me said it’s a head scratcher and we can’t help I’m really sorry
Just said my advice to you if take it to someone who is a timing chain specialist or equipped to do the job

 

[Seanwinder22]

And finally:

Here is a diagram I drew to show the time relationship between the crankshaft position signal (which has a "glitch" twice per crank revolution) and the camshaft position sensor signal (which has a clear pulse once every two crank revolutions). The signals are diagrammatic, but you get the idea. The ECU can determine when it is Cylinder 1 which is at top dead centre on the compresssion stroke, and then just counts 1,3,4,2,1,3,4,2 etc. to determine the rest of the sequence. The fuel injection is timed according to the crank signal, as this is the more accurately timed.

The ECU can also check that the timing of the cam signal is not too early or late compared to the crank signal, and will throw an "incorrect relationship" P0016 error code if it deems it to be too far off. I don't know what the acceptable range is, but I would guess at something like plus or minus 5 crank degrees. If the chain was fitted a tooth out on the crank or intake cam sprocket then (assuming the engine started) the 14 degree crank error would immediately trigger this code. If the ECU can't find a satisfactory cam signal at all it will throw a P0340 or P0341 error code, it MAY also throw P0016 because if there is no signal then there is by definition an "incorrect relationship".

Whilst walking the dog I got to wondering. These chains don't wear out as a function of time, so don't need changing every 5 years like a belt. They are a mature and reliable technology which is supposed to last for a very long mileage, and some people have reported over 200,000 miles. Eventually the day will come when the chain has worn and stretched enough to trigger a P0016. But why has the previous owner gone to all the trouble and expense of having it changed so early at only 78000 miles ? Is there some problem with the sensors, sensor wiring, sensor position/alignment, chain sprockets, sprocket keyways, chain tensioner, chain tensioner oil supply or whatever which has caused a sensor alignment warning, and the chain has been changed to no avail in an attempt to fix it ? Is it possible that the engine is operating almost at the limit of acceptable error (say +/- 4 degrees), so it doesn't take much extra timing shift to push it "over the edge" ? I fear that just changing the chain again will get you no further, and a more detailed investigation is needed by someone with the right skills.

thanks for the reply appreciate it
I have had a auto electrian on the van who carried out the continuity tests to the cam and crank and Ecu says all fine
It was with them 2 days he phoned me said it’s a head scratcher and we can’t help I’m really sorry
Just said my advice to you if take it to someone who is a timing chain specialist or equipped to do the job

 

[Seanwinder22]

And finally:

Here is a diagram I drew to show the time relationship between the crankshaft position signal (which has a "glitch" twice per crank revolution) and the camshaft position sensor signal (which has a clear pulse once every two crank revolutions). The signals are diagrammatic, but you get the idea. The ECU can determine when it is Cylinder 1 which is at top dead centre on the compresssion stroke, and then just counts 1,3,4,2,1,3,4,2 etc. to determine the rest of the sequence. The fuel injection is timed according to the crank signal, as this is the more accurately timed.

The ECU can also check that the timing of the cam signal is not too early or late compared to the crank signal, and will throw an "incorrect relationship" P0016 error code if it deems it to be too far off. I don't know what the acceptable range is, but I would guess at something like plus or minus 5 crank degrees. If the chain was fitted a tooth out on the crank or intake cam sprocket then (assuming the engine started) the 14 degree crank error would immediately trigger this code. If the ECU can't find a satisfactory cam signal at all it will throw a P0340 or P0341 error code, it MAY also throw P0016 because if there is no signal then there is by definition an "incorrect relationship".

Whilst walking the dog I got to wondering. These chains don't wear out as a function of time, so don't need changing every 5 years like a belt. They are a mature and reliable technology which is supposed to last for a very long mileage, and some people have reported over 200,000 miles. Eventually the day will come when the chain has worn and stretched enough to trigger a P0016. But why has the previous owner gone to all the trouble and expense of having it changed so early at only 78000 miles ? Is there some problem with the sensors, sensor wiring, sensor position/alignment, chain sprockets, sprocket keyways, chain tensioner, chain tensioner oil supply or whatever which has caused a sensor alignment warning, and the chain has been changed to no avail in an attempt to fix it ? Is it possible that the engine is operating almost at the limit of acceptable error (say +/- 4 degrees), so it doesn't take much extra timing shift to push it "over the edge" ? I fear that just changing the chain again will get you no further, and a more detailed investigation is needed by someone with the right skills.

Like you mentioned the engines and chains are supposed to be bulletproof
My lack of history even tho it’s full history paper work I don’t know issues it’s had in the past
I even got told why the chain replaced the first time or was it ? Did the dealer selling the van at those miles think by saying it’s had the chain done be a better sale ? Or did it get done correctly is what this mechanic I’ve had on it
He said maybe the first issue was in dead a stretched chain so was just the chain replaced no tensioner or anything else
The receipt does say £600 which that is CHEAP 9 month ago that’s very very cheap £850 is still cheap for this job on this van
Something is fishy to me very off about this dealer who has the van before the guy I’ve purchased off
The owner is a captain at East Midlands airport seems a very nice guy he’s still in touch with me actually said he will help pay
Because I had a few week then hit theses issues so I wasn’t happy
But like mentioned above was a full timing kit fitted and water pump
Did just the water pump have issues I just don’t know
I just know it runs but then will not at all
In fact it’s getting worse the more I try
At first it started fine now it’s stalling more
While driving earlier the engine light came on not done that before
I have a mechanic friend I went to school with but this is a motorhome his garage won’t take it in
Spoken to him a few hours this morning he said it’s not been done right or stretched chain
Even a tooth out he said it will run but stall and run and so on

 

[Anthony489]

Hi, I have dug out more information about timing.

Firstly, the crank sprocket has 20 teeth and the Cam sprocket has 40 teeth. So one tooth out is 18 crank degrees which is quite a large amount, enough to make a serious dent in engine performance or even prevent it starting at all.

Secondly, the Intake cam sprocket appears to have 5 cutout windows, which activate the Hall magnetic type Cam sensor as they rotate past its tip. There are 4 regular windows plus one offset one, presumably to identify cylinder 1. I have updated my waveform diagram to show what you would expect to see on an oscilloscope with the 3.0 Litre engine.

I found a cam kit online for Euro 5 engines which curiously has what appears to be one of the 4 regular cutout windows filled in. I may be barking up the wrong tree here, but it suggests that Fiat may have changed the design. I can imagine that if the earlier 5 window type was fitted in error, the ECU might struggle to interpret the signals it was presented with. Something to investigate maybe ?

 

[Seanwinder22]

Hi, I have dug out more information about timing.

Firstly, the crank sprocket has 20 teeth and the Cam sprocket has 40 teeth. So one tooth out is 18 crank degrees which is quite a large amount, enough to make a serious dent in engine performance or even prevent it starting at all.

Secondly, the Intake cam sprocket appears to have 5 cutout windows, which activate the Hall magnetic type Cam sensor as they rotate past its tip. There are 4 regular windows plus one offset one, presumably to identify cylinder 1. I have updated my waveform diagram to show what you would expect to see on an oscilloscope with the 3.0 Litre engine.

I found a cam kit online for Euro 5 engines which curiously has what appears to be one of the 4 regular cutout windows filled in. I may be barking up the wrong tree here, but it suggests that Fiat may have changed the design. I can imagine that if the earlier 5 window type was fitted in error, the ECU might struggle to interpret the signals it was presented with. Something to investigate maybe ?

Thank you for all the information appreciate it but this is our my depths not being a mechanic I just don’t understand but I’m saving images and copying posts
The van as been transported today to a garage that deal in timing chain issues. fingers crossed this is the last place it visits they quoted £810 timing chain and kit which is tensioners and so on plus water pump replaced . I checked on paper work I got back from the other garage checks was full diagnostic and cam and crank wiring to ground and Ecu checks all continuity checks , ground to chassis wire changed and area cleaned . Cam & crank sensors fitted with new. Oil change & filters
Wiring harness checked for damage all connectors and plugs checked for green wire or bad connection
All tests carried out came back inconclusive
Top mechanic of the workshop suggested timing issue is all that’s left to check … which it was him that said was the chain & timing ever changed in the first place or just a tensioner we just don’t know what’s happened
But… this was 9 months ago it run with no issues since was sold. This issue started when I purchased the van. the mechanic was right it’s a head scratcher definitely
all the information I’m getting I’m emailing it over but at the same time I just hope I’m not making these guys that have it now feel I’m not confident in them I just want it fixed! I just wanted to come on some forums and get some knowledge or even get some posts on here for the future. No matter what happens I will post updates when I find out 100%
Not many people have known issues like this happen like you mentioned on a fiat ducato 3.0 with low miles and chain issues is strange , but it can happen To any vehicle wrong oil being used not enough services on time. 78000 miles is not high but apparently 80000 miles is for a chain so I just don’t know
But a little research into buying vehicles hitting these miles I have noticed they all do say belt changesd or chain just been done it must put the buyer at ease
And to be honest my friend when I was buying this van did say … it’s in the 70s ask is the chain been changed so makes sense and dealers can’t be trusted I know this from experience when they have a mechanic working for them
All this is just not something I expected but it could be worse I could be paying the bill myself
I’m sure Monday I will know more
I just hope and pray these guys don’t do what you said change chain kit thinking that’s it So much else to check I’m told while they have the chain off and in that area

 

[Seanwinder22]

Hi, I have dug out more information about timing.

Firstly, the crank sprocket has 20 teeth and the Cam sprocket has 40 teeth. So one tooth out is 18 crank degrees which is quite a large amount, enough to make a serious dent in engine performance or even prevent it starting at all.

Secondly, the Intake cam sprocket appears to have 5 cutout windows, which activate the Hall magnetic type Cam sensor as they rotate past its tip. There are 4 regular windows plus one offset one, presumably to identify cylinder 1. I have updated my waveform diagram to show what you would expect to see on an oscilloscope with the 3.0 Litre engine.

I found a cam kit online for Euro 5 engines which curiously has what appears to be one of the 4 regular cutout windows filled in. I may be barking up the wrong tree here, but it suggests that Fiat may have changed the design. I can imagine that if the earlier 5 window type was fitted in error, the ECU might struggle to interpret the signals it was presented with. Something to investigate maybe ?

Also just been thinking about what you said earlier 5 window type was fitted in error would that run for 9 months with no issues or codes ? when I bought the van was no issues or codes I had it checked out. surly also let’s say it’s true the timing was changed when they say would it work with no issues or codes too ? Just chatting with my friend he’s come to say me he’s the head mechanic at Citroen in my area. He’s convinced it’s a stretched chain or tensioner
He’s done some digging today and apparently these bonnets leak BAD which I did notice the scuttle tray had been done and pipes all over from the sill
So because they leak in the casing area in cold weather they can freeze
On a cold morning you can start up as normal with the chain froze in parts and it can jump
Just what he’s found out today so these bonnets need the upgrade done to stop all leaks or injectors are covered also in water
that’s just one issue. or what he thinks timing is out definitely stretched or jumped a tooth which will run but bad but stall
Tensioner or a pulley bolt with vibration is known to shake loose
I’m just praying these guys do give it a really good check over
I don’t know anything about the job only it’s a good 5 to 8 hours depending on tools and the mechanics on it and experience
have you got any information I can forward over to them what to check which doing the chain
The quote says timing chain kit and water pump so I’m thinking that’s chains and tensioners and rail only no pulley or bolts or what you mentioned the second post
Thanks buddy appreciate what’s come in upto yet

 

[Anthony489]

Hi Sean

I appreciate that you are reliant on others to carry out the nitty-gritty, so feel free to pass on any of my comments to whoever is doing the work !

The "iced up timing belt" effect has been reported a few times, and can cause it to jump a tooth. I am rather doubtful if a metal chain would behave the same way, and even if it did jump a tooth it would then throw the timing off by a whopping 18 crank degrees. This is such a large amount that I suspect the engine would run very poorly (if at all) and the P0016 error would be immediately triggered all the time, not just now and then.

Further digging has revealed that the P0016 error code can be triggered on some engine designs by a discrepancy as small as 3.6 degrees, i.e. equivalent to only one fifth of a sprocket tooth interval. This is the sort of small amount that could be caused by a badly worn (stretched) chain, but your chain is nearly new. However, the chain is held in tension on its "slack" side by a tensioner operated by the hydraulic pressure of the engine oil. Wear in this tensioner or some problem with its oil supply (blockage ?) could conceivably cause the issue you are seeing, so I'd recommend the tensioner and its small oil supply gallery is at least looked at. Was the tensioner replaced when the chain was last done ?

All the above assumes that the ECU is getting correct signals from the Cam and Crank sensors, and that we are genuinely dealing with a mechanical timing error. Given the effort that has been directed at the sensors and their wiring, maybe its time to push them lower down the "suspects list" and revisit the mechanics.

Good Luck !

 

[Seanwinder22]

Issue fixed the chain had been previously done but apparently done wrong , chain looked tight on top but slack below timing was out but it’s fixed all codes went and now drives fine, I did notice before it went in the garage it only just went to 2000 revs on idle now you give it some throttle it goes way over 3000 no noises or stalling

 

[Seanwinder22]

I will get more information off my mechanic when it goes in for the mot so I can post on here to help someone out. I think everyone what comes to these brilliant forums for help need to post findings when fixed it really helps future posts 100%
but the issues I had was warm start issues and stalling
Run fine first start and drove fine but when you came to a stop turned the key off it would not start
If you get in this this situation unplug your camshaft sensor only the connector not the sensor lol if your van starts it’s either the sensor or timing like my issues
Apparently on my van with 3 chains The timing can be 1/2 a tooth out your van will run but won’t run right and throw a code p0016 po340 bank 1 correlation it’s bad news either way because it’s a timing issues it’s the worst out the 4 issues cam or crankshaft sensor or wiring is the first issues but the very first thing you should do is get a auto electrician out it will save so much money and time don’t do it the way I did going to a garage they will change part after part crossing fingers . Then say you need a electrician get wiring checked first even the guy that comes can get parts and change if needed it will save you time and money honestly
First place to check on this van is passenger headlight your Ecu and wiring loom near headlight check for chafing also check connectors for corrosion mine had issues also but once cleaned up was fine

 

[Tallykissangel]

What an excellent piece of detective work on everyone's part. Hats off to the Citroen mechanics. makes you wonder should n we get our fiats service by Citroen garages?
well done.

 

[Seanwinder22]

What an excellent piece of detective work on everyone's part. Hats off to the Citroen mechanics. makes you wonder should n we get our fiats service by Citroen garages?
well done.

I agree amazing work on these forums Anthony above was spot on about the issue… my chain was slack but from below it , from above it looked fine and tight . From below it was slack obviously a tensioner which now makes sense with a oil issue. on the diagnostic tests a oil sensor kept coming up low oil even tho full
Pointing to a blockage which then gave issues to tensioners which then throw the codes
Wasn’t a expensive job because the chain had been done , but my mechanic said it wasn’t done right so it was a case of getting the chain tight below too either way it was a bad experience with lots of wasted parts
One thing I did learn from it all when it comes to a motorhome always take it to a big truckers haulage garage they have more knowledge of these issues then your town garage

 

[Charlie 58]

Hi all, i am new here,
i just wanted to thank the contributors and add to the thread ,
hoping it may help someone in the future, and confirm it was not an isolated issue,
as i am actually doing the repair myself and add some detail including photos,
there is not much out there , and i came accross this thread while testing the wiring and sensors,
i am going through the same no hot start, P0340 repair at the moment on my hymer 3.0 Ducato,

i have had the motorhome for 12 1/2 years, its always had shell oil and bosch or mann filters,
i fitted a replacement aftermarket full chain and tensioners kit approximately 5 years ago,
it was just a start up chain rattle that got louder, no warning lights or fault codes,

the current pO340 and hot start fault only developed recently on a long euro trip, no noises,
i ran some tests volt dropping the wiring from cam sensor to ecu with a 21 watt bulb load
all 3 wires were ok,
for reference orange is 5v+, white grey is ground, white yellow is signal,
the scope trace anthony put up was useful , my cam timing looked retarded when comparing my pico trace,
i have just got the engine stripped to access the crank timing pin hole, see photo the cam pin wont go in,
the inlet cam is just about half a tooth retarded, the exhaust cam slightly more,
the lower and upper timing chain tensioners are almost at full travel, the upper is past the ratchet,
when turning the engine to align the timing the chains were whipping and clicking loudly against the guides
with the varying camshafts pressure,
i will update when i have got some photos of the chain runs when the weather improves,