Yes, I added to this thread because it was the only one that exactly matched the car’s symptoms. I’ll be able to do some more testing over the coming days, but yes the Bosch battery is brand new and I doubt it is causing this issue (but I could refit the old one to check - also Bosch).
Technical Stalling when using windows
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Technical Stalling when using windows
Great
At the moment we have very little to go on, electrical, electronic or a running issue
It's a matter of testing, then with results pick a direction to go or further testing
Otherwise it can get expensive, yes I know it's not a Fiat
This car had a
New PCV
Baterry
Plugs
Recon alternator
Vacuum lines
Throttle body clean
New Throttle Body
For it to turned out to be low compression
But it is a great example how guessing does not always pay off
the same symptoms can have many different causes
A lot of what was changed on the above car could have been easily avoided via testing
In fact somethings were tested okay but then changed anyway in hope
I usually leave aircon on all the time, but in fact it has been off for the last few days when I have been experiencing these issues. On a run tonight (with engine warm) I switched the aircon back on and at idle the revs were stable at approx 800 RPM. Lots of window operations but I couldn’t make the car stall.
So the problem may have been there for some time, but the aircon being on must help to avoid the slight dip in revs under electrical load which usually causes the car to stall.
So the problem may have been there for some time, but the aircon being on must help to avoid the slight dip in revs under electrical load which usually causes the car to stall.
The engine computer alter how the engine runs
I take it the revs are
750 ac off
800 ac on
Is this correct
I take it the revs are
750 ac off
800 ac on
Is this correct
I will check (lots of things to do now!) and report back. Those extra 50 revs seem to make a huge difference, so I want to slowly go through things including the earth strap and ignition leads. As posted earlier, I changed the spark plugs but find it difficult to guarantee that the boots on the ignition leads are seated correctly, so I now have some spark plug pliers to do it properly.
I did that test today...300mV while cranking.
The issue remains, normal idle measured with MES is 750rpm, increases to 850rpm when the aircon clutch is engaged.
Brand new battery. Earths seem ok with continuity checks.
Additional electrical load at idle causes the car to stall. At night with dipped beam on, this also includes using the brake pedal. Winding a window to the stop will also cause the car to stall. It's a bit better with aircon but can still happen.
Alternator charging voltage is approx 14.1V. MES measures the ECU voltage as 13.5V. No fault codes logged.
I'm not sure if it is an engine or electrical issue. Otherwise the car drives fine, I can overcome this problem by applying slight revs when stopped but it's not ideal and will occasionally still stall. I've had the car for nearly 5 years and this has only started happening in the last few weeks.
I have the free version of MES and can run any graphs if necessary, but for now I'm pretty stumped as to the cause. I don't want to change random parts, but is there a way of testing the alternator more thoroughly?
As ever, grateful for any advice!!
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A little high but acceptable
750 correct
850 with aircon correct
Yep need to get to the bottom of thid
14.1V at idle no load is correct
A voltage drop at the ECU is expected, It does vary with software, Torque Lite, is normally 0.1V and using delphi a little more around 0.2V, I don't have the car here to see what MES says
No neither do i at the moment
We need to load the electrical system now and see if the regulator is working and is being controled by the body computer correctly
Should be around 13.8V with the rear window heater and main beam at 750 rpm
Obviously you will have to raise the revs a bit first to stop it stalling and putting the aircon on as it helps
Using MES you should be able to clear the adaptive memory so it can relearn the throttle position again
Is the throttle flyby wire or cable operated
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Has it been serviced?
Specifically, have spark plugs been changed?
Specifically, have spark plugs been changed?
Fitted new NGK plugs about a month ago, could tie in with when these symptoms started.
I did extract the plugs this weekend, looked like an even condition across all cylinders, so replaced them. I haven't specifically checked the gap as previously new plugs were to spec (but perhaps I should actually check).
Also replaced the ignition leads this weekend, as they were cheap, but no change to symptoms.
NGK are OEM. If you buy cheap from Ebay you probably only got a 50/50 chance they are genuine
There are three types fitted depending on year
I have never known a denso, champion, Bosch or NGK gap to ever be out from new
There are three types fitted depending on year
I have never known a denso, champion, Bosch or NGK gap to ever be out from new
Sorry I read the thread wrong I thought
2008 Fiat Panda Active 1.1 a cable throttle
But it's actually a
My 2006 1.2 Dynamic
With flyby wire
We need to eliminate the easy first
But I don't think it will be an electrical fault
When using most accessories it is normally for the RPM to drop
The engine computer detects the drop and almost instantly increases the revs back to normal avoiding a stall
There is a limited amount of adjustment the computer can make,
The computer adjust the idle by opening the throttle plate, somewhere between 0 and 10 degrees, yes I made those numbers up. Now if their was a build of carbon restricting the airflow and the throttle plate is already at 10 degrees just to maintain a good idle, as soon as we operate say the electric windows the car will stall
Reading the throttle plate angle with a scan tool and getting a baseline before touching anything would be my first port of call
2008 Fiat Panda Active 1.1 a cable throttle
But it's actually a
My 2006 1.2 Dynamic
With flyby wire
We need to eliminate the easy first
But I don't think it will be an electrical fault
When using most accessories it is normally for the RPM to drop
The engine computer detects the drop and almost instantly increases the revs back to normal avoiding a stall
There is a limited amount of adjustment the computer can make,
The computer adjust the idle by opening the throttle plate, somewhere between 0 and 10 degrees, yes I made those numbers up. Now if their was a build of carbon restricting the airflow and the throttle plate is already at 10 degrees just to maintain a good idle, as soon as we operate say the electric windows the car will stall
Reading the throttle plate angle with a scan tool and getting a baseline before touching anything would be my first port of call
Yes, it’s a 2006 1.2 Dynamic. It has a normal throttle cable.
Today’s experience: started on third attempt (usually starting is reliable). Drove 90 miles on motorway and A roads to work. Parked in car park, at idle. Switched on rear window demister (to test under electrical load). Instant stall.
The only recent major fault has been the crankshaft sensor - in December I couldn’t start the car. Crankshaft sensor was identified as an ECU fault (MIL on). Replaced the part and that cured it and allowed me to start the car.
Otherwise I have changed the battery, plugs and ignition leads.
I will try to gather some more data, eg throttle plate angle as above. If I continue randomly changing parts then I might try the coil packs next, but I’m keen to continue with diagnostics if I can, rather than waste money.
Today’s experience: started on third attempt (usually starting is reliable). Drove 90 miles on motorway and A roads to work. Parked in car park, at idle. Switched on rear window demister (to test under electrical load). Instant stall.
The only recent major fault has been the crankshaft sensor - in December I couldn’t start the car. Crankshaft sensor was identified as an ECU fault (MIL on). Replaced the part and that cured it and allowed me to start the car.
Otherwise I have changed the battery, plugs and ignition leads.
I will try to gather some more data, eg throttle plate angle as above. If I continue randomly changing parts then I might try the coil packs next, but I’m keen to continue with diagnostics if I can, rather than waste money.
Is the cranksensor close enough to the (I think) crankpully? I could imagine a too low signal when an electrical load is introduced. And I think that would not give a faultcode.
Just thinking out loud...
Distance as small as the thickness of a creditcard would be right.
gr J
Just thinking out loud...
Distance as small as the thickness of a creditcard would be right.
gr J
Weird I had an 06 1.2 dynamic but it was flyby wire both UK
We should be able to diagnose this without randomly changing things
The system has an idle control valve, we need to its on time, Should be around 50% give or take 15%, I have never checked one for the exact value
Also it's adaptive value, I will guess that this is maxed out
Try temporarily disconnecting the blue pipe to the right of the throttle body, it should run fine just to test with, it's a quick connet type fitting
I like this theory, but it's not possible to adjust the distance between the sensor and the pulley. It's held in a fixed position by a 10mm bolt. I will check it though.
Evap for emmisions control
Unlikely but if there is extra fuel entering the idle control would have to open more
It's a common for them to cause an idle issue
My car 1.2 69hp flyby wire engine runs fine with it disconnect
It will only takes a few minuites to eliminate something else
I warmed the engine up and checked a few settings with MES this evening. I was looking for more info on the step motor in the throttle body which adjusts idle speed.
First, the Idle actuator / Step motor testing function on the MES Actuators tab works fine, engine speed rises and falls twice.
Second, on the Parameters tab, the idle actuator (I understand this to be the 'demand signal' on the step motor) rises and falls with electrical load, from a setting of about 55 with no load through to 80+ as the electrical load increases. It reads 83 in this picture.
However the step motor opening and idle actuator opening (bottom two ticked parameters, on 0.0% and 13% respectively) do not appear to move in line with the demand signal.
It seems strange that the mechanism appears to work fine from the Actuators tab, but then doesn't work under real electrical load.
At the moment I can't conduct a self-adaptation reset as I only have the free version of MES (which prevents that action). Of course I'd buy the full version if this action might help to cure the issue.
I have tried disconnecting the step motor cable from the side of the throttle body and cleaning the plug/socket but that has not made a difference.
First, the Idle actuator / Step motor testing function on the MES Actuators tab works fine, engine speed rises and falls twice.
Second, on the Parameters tab, the idle actuator (I understand this to be the 'demand signal' on the step motor) rises and falls with electrical load, from a setting of about 55 with no load through to 80+ as the electrical load increases. It reads 83 in this picture.
However the step motor opening and idle actuator opening (bottom two ticked parameters, on 0.0% and 13% respectively) do not appear to move in line with the demand signal.
It seems strange that the mechanism appears to work fine from the Actuators tab, but then doesn't work under real electrical load.
At the moment I can't conduct a self-adaptation reset as I only have the free version of MES (which prevents that action). Of course I'd buy the full version if this action might help to cure the issue.
I have tried disconnecting the step motor cable from the side of the throttle body and cleaning the plug/socket but that has not made a difference.
Is this not just a limitation of the free version?
I don't think so, the only limitation appears to be that you can't perform a self-adaptation reset with the free version (and it can only remain open for 20 mins).
The TB/step motor testing function on the Actuators tab seems to work fine, and the car responds as expected (which would imply that the throttle body and built-in stepping motor are fine). But I can't observe that behaviour when I monitor the relevant parameters directly - the demand signal increases/decreases in line with electrical load without a corresponding change in idle speed.
