Technical Cutting Out / stalling 1.2 2006 Punto

[oldfudger]

Hi all,

my daughters 2006 Punto 1.2 starts runs fine for around 5-15 mins then wont hold tick over, then doesnt start to well, need to put ur foot flat to floor while turning key. Fitted a second hand/scrapyard throttle body today no better, maybe slightly worse.

any help, ideas for my dad to follow up ?

I need the car for my first full time job i started this week

thanks

 

[oldfudger]

its 1.4 sorry, anyone with ideas, direction

 

[Bernievarian]

Seems like it's temperature related, can you confirm this ?

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)

 

[oldfudger]

Well the car starts better and doesn't stall when first started only once its been ticking over / driven for approx 10 min (engine is warmer). Thanks ! Any ideas ?

 

[Bernievarian]

Definitely temperature related issue then !

When engine's warm and you try to start it, does it smell petrol at exhaust ? What is you temp gauge reading ? What is your mpg ?

My guess is that the Engine Control Unit (ECU) still thinks that the engine is cold and therefore enriches the mixture to compensate for poor petrol vaporization and droplets deposit on cold engine walls. When you full press the pedal you increase the air amount so it vent and kinda "wash" the excess petrol and the engine eventually starts. I bet the engine cranking speed increases (like if it aims to start) a while before finally starting (when warm).

Please confirm what type of engine it is so we can check what sensors are fitted on ...

BTW: ensure there is NO restriction in the air flow to the engine (clogged filter...)

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)

 

[oldfudger]

Definitely temperature related issue then !

When engine's warm and you try to start it, does it smell petrol at exhaust ? What is you temp gauge reading ? What is your mpg ?

My guess is that the Engine Control Unit (ECU) still thinks that the engine is cold and therefore enriches the mixture to compensate for poor petrol vaporization and droplets deposit on cold engine walls. When you full press the pedal you increase the air amount so it vent and kinda "wash" the excess petrol and the engine eventually starts. I bet the engine cranking speed increases (like if it aims to start) a while before finally starting (when warm).

Please confirm what type of engine it is so we can check what sensors are fitted on ...

BTW: ensure there is NO restriction in the air flow to the engine (clogged filter...)

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)

Yes when engine is warm (it has reached halfway on gauge and fan has come on once) you have to put ur foot to floor to get it to eventually start, there is a smell and little smoke but doesn't tick over long. there are no restriction to air flow. engine is a 1368cc active sport. thanks for your time and advice

 

[Bernievarian]

8V, 16V, even T-Jet ?
exhaust pipe color ?
MPG ?
last service ?
smells petrol ?

 

[oldfudger]

8V, 16V, even T-Jet ?
exhaust pipe color ?
MPG ?
last service ?
smells petrol ?

8v

mpg 36/38

last service - oil, oil filter air filter last week. before that ?
yes some petrol smell

exhaust slight smoke (white)

 

[Bernievarian]

last service - oil, oil and air filter; how about spark plugs ?
Some petrol smell indicates a too rich mixture or misfiring.
Mixture is controlled by tyhe ECU according to various sensors and conditions, here's an excerpt of the eLearn :

Combustion - lambda sensor check
In EOBD systems the Lambda sensors, all the same type but not interchangeable, are positioned one before and one after the catalytzer. The sensor upstream of the catalyzer determines the control of the mixture strength known as the 1st closed loop.

The sensor downstream of the catalyzer is used for the fault diagnosis of the catalyzer and for modulating the 1st loop control parameters.

The second loop is therefore adaptive to make up for production discrepancies and slight drift that the response of the sensor upstream of the catalyzer could experience due to ageing and contamination.

This control is known as 2nd loop control (closed loop).

Operation when cold
In these conditions there is a natural weakening of the mixture as a result of the poor turbulence of the particles of fuel at low temperature, reduced evaporation and strong condensation on the internal walls of the intake manifold, all of which is exacerbated by the increased viscosity of the lubricant oil which, as is known, increases the rolling resistance of the engine mechanical components at low temperatures.

The electronic control unit recognizes this condition on the basis of the coolant temperature signal, increasing the basic injection time.

Whilst the engine is warming up, the electronic control unit also operates the stepping motor which determines the quantity of air required to ensure that the engine does not cut out.

Have you got the possibility to do some measurement (on coolant sensor) or better, run a MES diagnostic on your car ?

Mayber some menber in your vicinity could perform this MES stuff, anyone ??

BRs, Bernie

 

[oldfudger]

i will look into it thanks

 

[oldfudger]

what is procedure to check coolant sensor (volt meter ?)

I can then get car put on diagnostic later in week

 

[Bernievarian]

You'll need an ohm-meter and a kitchen thermometer.
- remove the sensor (engine cold), some water will spill, don't worry
- connect the ohm-meter to the two terminals
- place the sensor in cold water in a cattle (do NOT immerse the plugs !!)
- heat the water and read the ohms value as the temperature increase
- compare to the table below ...

One can do the same check on the MAP (air pressure & temp) sensor, the expected values are the same and it'd be a good opportuniuty to clean that MAP sensor ... Measurement to be done between pins 1 and 2 (Nero/Bianco , Bianco/verde)

O-C basic tests such as coolant level, battery charge and earthing have been sucessfully passed, do they ... ?? Please Confirm.

BRs, Bernie

If someone here helped You fix -or better, understand- your issue, hit the thanks icon @ bottom right corner, it's free and makes us feel helpy ;-)

 

[oldfudger]

O-C basic tests such as coolant level, battery charge and earthing have been sucessfully passed, do they ... ?? Please Confirm.

yes all ok