Means the next Pope was chosen!
Technical Engine issue
- Thread starter Zekarn
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Engine issue
Especially with no brakes after all the fluid was burnt off.Wow! That sounds... thrilling!
You should have done drifts with the car in that state!
By the way we were doing drifting before all you youngsters were born in our old six cylinder rear wheel drive Fords and Vauxhalls with cross ply tyres.
Lambda.csv : test at idle with the instability present
Lambda2.csv : test while driving, no instability present at idle (test start with temperature gage at 1/4 of its max value)
I can check for older recordings if I had record the lambda sensor voltage
I have a recording of the catalytic converter because I had check it, it is verry clean. I don't have diesel smell coming from the exhaust. What can cause the DPR to be faulty and trying to regen ?Generally white smoke on diesels, if smelling of diesel is unburnt fuel caused by low compression or if only just started then heater plug fault and it will smell of diesel.
These smoke tests can be done with car stopped and someone bringing the revs of the engine up whilst you check the exhaust smoke.
If the white smoke is real;ly choking but doesn't smell of diesel then it points to a DPR fault trying to do a Regen.
Apart from that if black smoke it points to excess diesel or not enough air/oxygen from the turbo.
If "blue" smoke and smelling of engine oil then usually piston wear.
The only other white foul smelling smoke I have ever seen was over 50 years ago on an Alfa Romeo Guilietta with a faulty brake servo which drained the brake master cylinder into the servo and the vacuum sucked it into the cars inlet. Servo design is different these days so unlikely to be that.
I don't see blue smoke but I have a lot of oil over the flap body, just before the intake manifold (I don't know were the oil came from)
I may have undertorque the lambda sensor when I set it back in place
I will check it tonight/tomorrow morning, when it is cold again
Is the lambda value 327,675 always there? What you recorded isn't helping much.
Do a graph with parameter you want shown (lambda pre cat and after cat signal voltage in this case), stop the recording when screen is full and take a picture, print screen, not save it as csv. To show something like this
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If it has a DPF they can fail or block needing Regens due to short journeys and slow speeds around town usually, but they fail with age/high mileage also.
Maybe a photo of the oil around flap area?
Oil could be coming from the turbo or wear in engine.
If the smoke is burning oil it is more blue than white and will smell of old engines.Also if piston wear causing it then it may also give low compression and rough running until warmed up a bit.
There used to be a joke about it when people came into a garage with an engine burning oil etc.
The mechanic would diagnose it as piston broke and the driver would say "yes, story of my life", as in pi**ed and broke/drunk and no money.
Sorry for the delay, I had a rude shift last night. Here are the screen capture. I don't know what start the lambda but it don't seem to measure before a certain event happened. Same name as before,
Lambda.png : test at idle with the instability present; Lambda2-X.png : test while driving, no instability present at idle (test start with temperature gage at 1/4 of its max value)
Ah a DPF, I was thinking of the catalyser that can also cause issues if clogged. As mention earlyer I don't have one, it was a requirment when I choose my doblo
Sorry I had'n remember to do a presure log yesterday, I will try to do it tonight
It shouldn't be a failing turbo, my dad checked it when we have change a rubber pipe in the intake (see picture from ePER) and it had no play at all or signs of failure. And my engine don't burn/loose oil/mix it with water, my oil level is still perfect from last oil change (08/2025, no oil refill) and when I change it it have the good color/consistency. Coolant is still at a good level, don't had decrease level from the last 2 years and don't had change color/consistency. I have a power stearing oil leak but it came from the stearing rackOil could be coming from the turbo or wear in engine.
If the smoke is burning oil it is more blue than white and will smell of old engines.Also if piston wear causing it then it may also give low compression and rough running until warmed up a bit.
There used to be a joke about it when people came into a garage with an engine burning oil etc.
The mechanic would diagnose it as piston broke and the driver would say "yes, story of my life", as in pi**ed and broke/drunk and no money.
For the low compression part I wanted to do a test 1,5 year ago but my tools supplier was too expensive and my dad have a kit, I will try to borrow it and try
Update on my issue : when the engine is cold and I started it for 2-3 min (and done 500m-1km), engine stall and stop when I try to go after a stop despite being light on gas and clutch pedal. It don't seems to happened again after a restart
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You don’t have a DPF or a catalyser?
I have a catalyser with a lambda on it but not a DPF (if I'm not mistaken about the English names)
Just one lambda on it? Isn't a second one there, after catalyser?
The graph you did... I don't know what that is, but surely must be something else than catalyser lambda's voltage. Voltage is too high for that.
Anyway... I asked for a graph because I had the exact problem like yours. Idle RPM would drop when engine was warming up. I noticed first that it was related to electrical consumers and issue got better after cleaning the ground lines, but eventually came back. I identified the real cause was the O2 sensor (lambda) after cat and putting another lambda sensor fixed it. Engine runs well now.
I covered that in this topic
BCM (Body Computer Module) ground and other electrical gremlins | FIAT Punto (Mk2/2b)
So... what made me look for rear ground connection. I felt again the RPM idle drop while engine was getting hot. Drop was ever so slightly, I asked my wife and son afterwards if they've noticed it, they were in the car too. And they didn't. But there was a drop, be it slightly. And it turned out...
www.fiatforum.com
PS: mine is petrol.
According to ePER, MES and what I have been able to see and understand on my car, I only have one lambda sensor which is located directly on the catalytic converter (before the honeycomb patern filter). For me the incoherent value is just that the sensor isn't powered yet or that no readings are done on it. I had a similar result on the temperature sensor in the MAF when it was unpluged (I had a -40°C with no variations)Just one lambda on it? Isn't a second one there, after catalyser?
The graph you did... I don't know what that is, but surely must be something else than catalyser lambda's voltage. Voltage is too high for that.
Anyway... I asked for a graph because I had the exact problem like yours. Idle RPM would drop when engine was warming up. I noticed first that it was related to electrical consumers and issue got better after cleaning the ground lines, but eventually came back. I identified the real cause was the O2 sensor (lambda) after cat and putting another lambda sensor fixed it. Engine runs well now.
I covered that in this topic
BCM (Body Computer Module) ground and other electrical gremlins | FIAT Punto (Mk2/2b)
So... what made me look for rear ground connection. I felt again the RPM idle drop while engine was getting hot. Drop was ever so slightly, I asked my wife and son afterwards if they've noticed it, they were in the car too. And they didn't. But there was a drop, be it slightly. And it turned out...
I have check your post, your is more recent than mine, it can be the reason why I only have one and you have 2
I will check if I can do a graph with an older doblo (diesel too) that is just a bit older (2W from 200 to see if it reacts the same way
I had am 2005 Fiat Doblo 1.9JTD 105hp that just had a EGR valve and a Particulate filter instead of a DPF so it just looks like a small silencer and has no pipes or sensors on it. Maybe you can post a photo of yours.
Yes, only one sensor was used for many years. If you can't see a second sensor physically, means yours has just the one.
The voltage you recorded puzzles me. From what I know, lambda sensors typical range can be
Narrowband measuring 0-1 V. That's what I have and I think yours should be the same
Wideband measuring 0–5 V (usually ~2.5 V center).
Your reading is way off to those ranges.
So the cause might be lambda sensor on yours, too. It's just very unclear for now, data you collected. Needs more investigation and a graph made on different car for comparison would help.
Here are the pictures with a picture of the whole engine
The reading is out of range up until the 2nd picture of the second graph (Lambda2-2.png) where the lambda tension (in yellow) drop from 32V to 1,7~2V. The part where the lambda is out of range can just correspond to the delay before the lambda value is read. According to eLEARN (the online version when it was available), I should have a heating element inside the lambda, I can add it to the list of check I must do on my doblo
Btw, I had print every electric diagram from online eLEARN for doblo 1.9JTD after 2003. The eLEARN available to download from the fiatforum doesn't mention the K40 (lambda)
Attachments
Anyway... sounds like there is a problem with lambda sensor.
So... I have been able to borrow another doblo 1.9 but it have no lambda on it so I cannot compare results. I also have real starting issues, I will check and maybe order a new lambda and a new EGR (I need to change lambda gasket but impossible to find it without the lambda)
About the fuel presure, everything seems right to me. I have compared results with the other Doblo and I don't see any difference (no sudden drop in fuel pressure, no timing difference between actual and wanted pressure when wanted pressure spike). I will check if I can do a leak test in a near futur
About the fuel presure, everything seems right to me. I have compared results with the other Doblo and I don't see any difference (no sudden drop in fuel pressure, no timing difference between actual and wanted pressure when wanted pressure spike). I will check if I can do a leak test in a near futur
