Technical Engine stalling

[Mypanda12]

Hi all, hope someone can help, I have just registered on this forum to help diagnose what is wrong with my Mums fiat Panda 2009. The issue is that it appears to intermittently stall, but strangely it seems only when the temp needle is below half way, so it runs fine when engine is warm. Starting from cold is no problem but after 4-5 mins of driving is often stalls. The battery is good.

My mum took it to garage and they checked it out, said it was a cambelt issue, so they replaced that (It likely did need replacing anyway as its done over 90K miles), and said its running fine and gave it back, but the issue persists. Then my Brother took it to another garage and asked them to clean out the throttle body, as someone told him that would fix the issue, but the issue still persists. Yesterday I replaced all the spark plugs, and all the HT leads, checked the two coil packs with a multimeter (both reading within spec), but again the issue still persists. The EML is not flashing up, and a quick scan with my cheapish reader reveals no pending codes, although there is x1 stored code (PO115,Engine Coolant Temperature (ECT) Sensor Circuit Malfunction).

Anyone have any ideas ? So far we have

Replaced cambelt (garage used a cambelt kit)
Cleaned soot from inlet manifold
Replaced Spark plugs
Replaced HT spark plug leads
Checked both the coil packs primary & secondary resistances (both readings are within spec)

Thanks for any help, the garages can find nothing wrong !!

 

[Mike1alike]

@Mypanda12, your problem is the IACV (idle air control valve) located on the throttle body. That controls the air intake when the gas pedal is not pressed.
Code for the part is MEAT & DORIA 84055.

 

[koalar]

Hi again. I cleaned the MAP sensor this afternoon, unfortunately It has not solved the issue, its still stalling regularly when engine is cold. I did notice that when restarting from a stall it is not instant like I originally suspected, it takes around 5-10 secs or cranking. I'm convinced its a temperature related as the appears to run fine when warmed up, and similarly if the revs are high when its cold. Would anyone consider it could be an issue with the coolant temperature sensor perhaps ?

No unlikely to be the coolant sensor

Its like the old day of when you had to manually pull out a choke when the engine is cold

The petrol vaporises much easier when it's hot, the car is much more tolerant to the wrong mixture,poor compersion or weak spark when the engine is hot

Your car is running the mixture, much to rich, I can't say why with nothing to go on

If you have an android phone buy a £5 elm327 Bluetooth dongle, it will serve you well for an future cars as well


Pull this pipe off

And see if it runs any better

It will smell a bit in the car turn the heating control to recirculating will help

 

[koalar]

I've had this. Brief stuttering at idle, I can't remember what caused it, pretty sure it is didn't fit any new parts, Fairly sure @irc had as well. Maybe a blocked are cracked breather

Trouble is more than one thing can cause similar faults

I be surprised if it was the idle control valve, it wouldn't explain the rich running, or why it holds an idle when warm

Highly likely to be the same as this one

Revs dropping leading to stall | FIAT Panda (Mk3)

Morning gang - hope you're all well and looking forward to the festive period :) I've got a problem with my 2012 model - partner was driving it the other day and told me the oil pressure light came on (yellow) and then the engine cut out. I checked the oil (which was low, in fairness), topped...

www.fiatforum.com

 

[Mike1alike]

I be surprised if it was the idle control valve, it wouldn't explain the rich running, or why it holds an idle when warm

It doesn't operate at its best anymore. It's not completely dead, still opens up but can't keep up with engine running. Low air on the mixture is exactly rich running, so it does kind of explain it.

 

[Mike1alike]

A diagnose tool to read the live data would help. It shows the numbers of 'steps' the IACV is opening and the intake manifold pressure.

 

[koalar]

Hi again. I cleaned the MAP sensor this afternoon, unfortunately It has not solved the issue, its still stalling regularly when engine is cold. I did notice that when restarting from a stall it is not instant like I originally suspected, it takes around 5-10 secs or cranking. I'm convinced its a temperature related as the appears to run fine when warmed up, and similarly if the revs are high when its cold. Would anyone consider it could be an issue with the coolant temperature sensor perhaps ?

Was it coved in oil or not

A photo would have helped

 

[koalar]

It's confusing at the moment as there's two identical threads except one flyby wire and the other cable operated

 

[irc]

Agreed - Probably loose/cracked breather pipe or airbox to throttle body seal, causing oiling up of the MAP sensor.
Seem to be coming across a lot of these lately.
Also check the airbox for cracks, especially the little stub for the breather pipe.

If you need replacement parts, beware - some suppliers have wrong part numbers listed for both seal and pipe. There are a few different sizes of seal, and lengths/bends of pipe for different versions of the FIRE engine.

 

[Mypanda12]

Thanks for the responses here, I will definitely take at good look at the possible suggestions best I can, but will have to be after Christmas. When I cleaned the MAP sensor it was oily, not dripping oil but a mist of it, I cleaned it with carb cleaner. Unfortunately did not take a pic as could not find my phone at the time. Have not had a chance today to check if throttle body is leaking but will do so when Im able. I did notice yesterday that the short hose from the underside of airbox has a split at the far end where it attaches to throttle body, if you can picture it, its split slightly at the end so a looser fit onto the throttle body. If the Idle Control valve is only a few pounds I will replace if an easy replacement. And sure Koala will remove that pipe and see if runs any better. Thanks so much for your time in responding, wishing you all a great Christmas. I will be back

 

[koalar]

Thanks for the responses here, I will definitely take at good look at the possible suggestions best I can, but will have to be after Christmas. When I cleaned the MAP sensor it was oily, not dripping oil but a mist of it, I cleaned it with carb cleaner. Unfortunately did not take a pic as could not find my phone at the time. Have not had a chance today to check if throttle body is leaking but will do so when Im able. I did notice yesterday that the short hose from the underside of airbox has a split at the far end where it attaches to throttle body, if you can picture it the its split slightly at the end so a looser fit onto the throttle body. If the Idle Control valve is only a few pounds I will replace if an easy replacement. And sure Koala will remove that pipe and see if runs any better. Thanks so much for your time in responding, wishing you all a great Christmas. I will be back

You ansewerd your own question

The split loose fitting pipe will be the cause

You might have to take the throttle body off

There's likely to a few cc of oil under there

Without removing the oil cleaning the map and put is back in will just be back to square one

Sorry I should have explained it better

I'd hang fire in the idle controle valve for now

There not that easy to change and you've not got a P0505 error code and it wouldn't explain why it's fine when got

You can clean it while the throttle body is off

 

[Mypanda12]

You ansewerd your own question

The split loose fitting pipe will be the cause

You might have to take the throttle body off

There's likely to a few cc of oil under there

Without removing the oil cleaning the map and put is back in will just be back to square one

Sorry I should have explained it better

I'd hang fire in the idle controle valve for now

There not that easy to change and you've not got a P0505 error code and it wouldn't explain why it's fine when got

You can clean it while the throttle body is off

Yes the pipe does reattach just its not so tight, it seems to slip on easily rather than need to push it on. Removing the throttle body and cleaning is certainly a task I could do, will I need any replacement gaskets ?. Will give that a go when I can and keep you updated. Thanks again

 

[Mike1alike]

I did notice yesterday that the short hose from the underside of airbox has a split at the far end where it attaches to throttle body, if you can picture it, its split slightly at the end so a looser fit onto the throttle body.

I can picture it. That's what they do. But that doesn't affect at all how the engine works because that goes onto TB where air intake is let in by the IACV and the butterfly. It cracked like that just lets crankshaft/engine block gases exit into atmosphere instead of going into engine again, combustion chambers.
Have a Merry Christmas yourself and get to it when you have time to it.
Replacing the IACV is quite easy and it is quite cheap. I'll guide you through if you want to.

 

[Mypanda12]

Thanks Mike, yep will keep thread updated. Happy Christmas

 

[irc]

. But that doesn't affect at all how the engine works

...but it does cause the MAP to get covered in oil, which does affect how the engine works.
Pretty sure here's a FIAT tech bulletin somewhere on here which explains the reasons, but I didn't bookmark it (or it could be in my pile of random tech bulletins that I haven't got round to scanning yet).
Its completely possible that it also has a problem with the IACV but its probably best to fix the one that you know you have, before introducing any new variables.

 

[Mike1alike]

but it does cause the MAP to get covered in oil

Cracked hose doesn't do that.
Au contraire, mon ami!
You guys put way too much emphasis on the oily intake manifold. That's just the way it is. It doesn't go quite as you fear it does.
If you want things to be good there make sure rocker cover oil channel isn't blocked and oil pump delivers properly.

 

[koalar]

...but it does cause the MAP to get covered in oil, which does affect how the engine works.
Pretty sure here's a FIAT tech bulletin somewhere on here which explains the reasons, but I didn't bookmark it (or it could be in my pile of random tech bulletins that I haven't got round to scanning yet).
Its completely possible that it also has a problem with the IACV but its probably best to fix the one that you know you have, before introducing any new variables.

I post it nearly every week

PDF Attached underneath

But it's like banging my head against a wall, hopefully Google will start picking this as a correct solution

The gasket under the airbox, how its mounted, pipes not blocked, or not leaking have to be correct otherwise It's effects the combined sensor pressure/temperature so obviously it effects fueling, in tur it effect running

Poor MPG, petrol smell from exhaust, especially on startup, difficulty restarting, sooty plugs, brief drop in revs, poor acceleration, stutter on acceleration

Quick and dirty test is to just remove the breather pipe from the valve cover, on the road a few wide open throttle up to the rev limit and immediately shut the throttle clears the intake manifold of oil

Well it worked on my 2011 1.2 69hp with a blown head gasket, until I got round to fixing it properly, sample size of one though

It's not the only cause, but it quick and easy to check

 

[irc]

Cracked hose doesn't do that.
Au contraire, mon ami!
You guys put way too much emphasis on the oily intake manifold. That's just the way it is. It doesn't go quite as you fear it does.

Actually it does (in any language)
"Oily intake manifold" is not great, but oily MAP sensor is definitely going to cause running issues.

EDIT:
Thanks @koalar.
Thats not the specific one I was thinking of, but it mostly says the same things. (I think it may actually have been a Ford Ka tech bulletin that I was thinking of, but same engine...)

 

[Mike1alike]

Actually it does (in any language)

Technically, cracked pipe lets the oil fumes go out, not into intake manifold...
That's what I was saying.

 

[koalar]

Technically, cracked pipe lets the oil fumes go out, not into intake manifold...
That's what I was saying.

No idea on the logic here

On the panda 1.1/1.2 there's no Air Oil Seperator
It's blow by gassed are just being sucked in

Atmosphere pressure is 100 kPa
Pressure in the intake at idle is 35 kPa at idle

That's a 65 kPa difference around 9 PSI

A drinking straw does not work very well if you put a hole in the side

The gasses stay in the pipe and condense out dripping oil into the intake manifold

 

[irc]

It's blow by gassed are just being sucked in

Description of operation from ELearn is not very detailed but it does give an overview.

Blow-by and other gaseous fumes are sucked through the small part of the pipe at idle, and the large part when throttle is open.

Anyway, off to do more Christmas things now, so...
Have a good Christmas, everyone.