Technical Cold start problem at first start

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Technical Cold start problem at first start

The lambda sensor is not ready at cold start. Starting is no closed loop control, it´s purely piloted. What about the battery? I had similar problems one mine (but it was a 1,2l), used platinium sparks, made it slightly better, then waited with ignition on some seconds before starting, but this made it only sometimes better. Then my battery died and I replaced it by a 50Ah battery from the diesel and since then the problem didn´t reappear...
 
have this problem for long time i try everything about fuel injection sistem, sensors, batery, batery strap etc.

In the future i will try with another ecu , but now i will try more custom fuel maps.

Dont know why she start and work ok for aproximaly 1 year from the custom map i put , and now reapear :)
 
I have a 1.2 litre POP.

Twice, when it hasn't been driven for a week and the second time not driven for 24 hours, it has not started without a lot of cranking. The engine turned over fine.

The first time this happened I gave up on the starter motor and roll started down a hill and it still took a while to fire up. I drove for five minutes fine, stopped for dinner nearby, then again it wouldn't start without maybe six attempts, a friend says it blew a bit of smoke on starting.

Then 10 days (900km) later it wouldn't start again, I cranked it about 15 times, it spluttered a bit a few times and then fired up and went fine.

I thought it might be dodgy fuel, water in the fuel, or fuel evaporating somewhere.

It has happened on hot days when the car has been sitting in the sun.
 
One possibility is a slightly leaking injector. The fuel rail doesn't automatically depressurise on shutdown, so if one (or more) of the injectors isn't completely closed, fuel could leak into the cylinder, causing a wet, smoky start.
 
I have a 1.2 litre POP.

Twice, when it hasn't been driven for a week and the second time not driven for 24 hours, it has not started without a lot of cranking. The engine turned over fine.

The first time this happened I gave up on the starter motor and roll started down a hill and it still took a while to fire up. I drove for five minutes fine, stopped for dinner nearby, then again it wouldn't start without maybe six attempts, a friend says it blew a bit of smoke on starting.

Then 10 days (900km) later it wouldn't start again, I cranked it about 15 times, it spluttered a bit a few times and then fired up and went fine.

I thought it might be dodgy fuel, water in the fuel, or fuel evaporating somewhere.

It has happened on hot days when the car has been sitting in the sun.

Thanks , but the problem is only if she stay much time , try to start and die in 2-3 sec, and at the second try it start ok, and all day work ok and start , wherever is stay 8 hours the stay fine.

It is about mmixture air from manifold , because if u spray start spray start for first time, if u hack the map senzor and freze of them , start ok ....
 
One possibility is a slightly leaking injector. The fuel rail doesn't automatically depressurise on shutdown, so if one (or more) of the injectors isn't completely closed, fuel could leak into the cylinder, causing a wet, smoky start.

Dont have this ,i put new injectors, try with new fuel line , not about depresurise. Last year try everything , and find a custom map and work about 1 year, and now the same problem apear

How a bag Ecu work ?
 
After few attemps of ecu maps, i find one good for the car and start ok :slayer:
Dont know why and dont know what is rong at this car !!!

I know if it is a bad or damage piece dont work and do this problems always , this car is :bang: so weird.


I attach a picture what i change
 

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Hi, i have Bravo 1.4 16v 120hp tjet 2009 270k km. I and all my friends have same problem. I read all of your posts. Except, if tank has fuel more then half it starts ok. Whenever fuel level drops below half it doenst start. It gets harder to start as it close to quarter. You succeed to start engine by removing the pin2 of map sensor with cold engine right?

What if i make a device with Arduino to disconnect the pin2 of map sensor while start engine and after 1 min or 30secs connects pin2 to map sensor again. I can program it to cut the pin2 connection if engine off by 6 hours or any other time period.
 
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the car start fine always when u ,,spray at the top of map sensor with frezz spray,or brake cleaner !

The car need a feedback from the pin 2 ,temperatur manifold interior ! Sometime start with this pin cut of ,sometime not.
I try a circuit bord ho disconect this pin for 20 second ,but not workind.
hZSpKLJ


I have in my mind and i order a board ho do,, down power adjuster' .In map sensor enter a 5 v , and at pin 2 send about 2-3 V back to ecu, i will use this 2 boards ,one to disconect the original pin2 and conect to adjuster and after 1 min to conect the original pin .

Now the car starts ok after the custom i made again, but i will prepare if the problem come back !
 

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the car start fine always when u ,,spray at the top of map sensor with frezz spray,or brake cleaner !

The car need a feedback from the pin 2 ,temperatur manifold interior ! Sometime start with this pin cut of ,sometime not.
I try a circuit bord ho disconect this pin for 20 second ,but not workind.
hZSpKLJ


I have in my mind and i order a board ho do,, down power adjuster' .In map sensor enter a 5 v , and at pin 2 send about 2-3 V back to ecu, i will use this 2 boards ,one to disconect the original pin2 and conect to adjuster and after 1 min to conect the original pin .

Now the car starts ok after the custom i made again, but i will prepare if the problem come back !

How many volt exactly you apply for pin2 to ECU after cut the connnection. 3.33v or 3.2v. you can simulate pin2 NTc resistor Signal with a simple pot 10k.

Pot has 3 pins. cut the connnection and Connect one pin to ECU Side of pin2. And Connect middle pint to ground. Voltage will change by the pot

Could you please measure the resistans between pin1(gnd) and pin2(NTc). You need to measure it twice for nice diagnose, first before sprey startsprey and second after sprey the startsprey. At 20c celcius outsite resistance should be near 2k.

Before and after sprey resistance measure is very important.
 
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I do a live test at pins of the ecu plug.
I know every wire from MAP sensor where did go in ecu plug.

The voltage depend of temperature, with MAP unplug is 5v standard, and with connected plug and engine coold is 3,33 V.
With the hot engine the voltage is 3.22 v.

But when i use the coold spray at senzor map and the voltage increase at 3,50-3,70 voltage the car start ok.

Hmm lambda,yes, but when u put the key on, the ecu read form some senzor Map and temp and do the mixt. The lambda read from exhaust, airflow.

If i dont find to remap the ecu, i tri a scam, a divice to lock the circuit of pin 2 about 1 min and than open.

Hi i made some calculations, when measure 3.33v outside temp should be about 16-17C degree, and when you freze map sensor you measure 3.7v and that means you drop temp to 6C degree( ECU thinks manifolt temp is 6C instead of 16-17C) so you able to Start car without problem. is my calculations about temp right?
 
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hy , the value is about there !
I dont know whay about 1 year work okwith that map , and then reapear, somebody say the ecu made a refresh at setting/map.
 
hy , the value is about there !
I dont know whay about 1 year work okwith that map , and then reapear, somebody say the ecu made a refresh at setting/map.

i made circuit with Arduino and Connect it to map sensor yesterday. i Wrote the code.

if engine doesnt run more than 4 hours than code activates the relay for 40seconds and adds extra 3k resistor to map sensors temp resistor. After 40 seconds deactivate the relay and map turn to normal operation. This means if engine doesnt run more than 4 hours ecu will assume it is between 0-5C degree and run with cold conditions for 40seconds. im in Istanbul and it is realy cold outside about 2c degree. So i will test the circuit for a few days and going to write the resuts.
if it doesnt work i have to keep tank at least half loaded every time. it is the only way for a smooth cold start
 
follow!


U say if u have half or more fuel tank start ok ? did u check the purge valve or vapor trap
Hello my friend,

I have same issue on 2008 Stilo 1.4 !

Changed:
- spark plugs (iridium)
- ignition coil
- battery
- fuel pump
- all fuel injectors and fuel rail
- starter motor
- alternator
- MAP sensor

Still persists. Regardless of weather, first start (after 5+ hours) always hard. Other start always immediately.

Any update on the issue from you? Have no idea what to change next
 
Hello my friend,

I have same issue on 2008 Stilo 1.4 !

Changed:
- spark plugs (iridium)
- ignition coil
- battery
- fuel pump
- all fuel injectors and fuel rail
- starter motor
- alternator
- MAP sensor

Still persists. Regardless of weather, first start (after 5+ hours) always hard. Other start always immediately.

Any update on the issue from you? Have no idea what to change next
You could contact a specialist who can read the live data when starting and see if there's an error in the fuel mapping ?
 
You could contact a specialist who can read the live data when starting and see if there's an error in the fuel mapping ?
Of course I could, but before I do, I wanted to find out if these issues were resolved, since they are 99% the same.
 
Hello my friend,

I have same issue on 2008 Stilo 1.4 !

Changed:
- spark plugs (iridium)
- ignition coil
- battery
- fuel pump
- all fuel injectors and fuel rail
- starter motor
- alternator
- MAP sensor

Still persists. Regardless of weather, first start (after 5+ hours) always hard. Other start always immediately.

Any update on the issue from you? Have no idea what to change next
Hi from CZ :),

I have the Fiat 500 2008 1.4i 16v 74kw - problem: after sitting for more like 5 hours (cold engine) - first start is like shaky bad and usually goes off. The second start is usually fine, like nothing was bad before.

Changed:
- spark plugs (from bosh to original NGK)
- battery
- cleaned fuel system several times
- MAP
- filters
- timing belt (Fiat specialist did it, so should be fine)
- oil change with engine flush

Nothing helped. What helps: Switch from 95 octane to 98 octane.
With ONO (you will know from CZ) or other "cheap" 98 octane car runs just fine, every start from full tank to empty is fine.
100 octane (Verva/OMV/...) --> doesn't work, same problem
- also works - 1/2 tank cheap 95 and 1/2 Shell Vpower 100
- VIF aditiv doesn't work only with 95
- now I bought Millers oils petrol power ecomax - should add about 2 octane number to cheap 95 and I will test it.


I was asking for some ECU tuning/update, nobody in CZ was able to answer. Some cars here (same ae and engine specs) works fine, some has the same problem.

I also asked mechanic, if intermittent cold start could be problem for car (catalytic converter or lambdas, starte, idk...) but they said, it is only minor issue and it should not harm anything.

Also, mechanic said, that some 1.4 T-jet have issues with gas quality, so... seems legit.

Only problem is, that for example 100 octane is easier to find, and 95 is much cheaper, so I hope some kind of additive will help us, so we will be "free" to visit any gas station we find. In other case I will buy some 98 from ONO to jerrycans and I will pour it into 500 at home :D
 
Hi from CZ :),

I have the Fiat 500 2008 1.4i 16v 74kw - problem: after sitting for more like 5 hours (cold engine) - first start is like shaky bad and usually goes off. The second start is usually fine, like nothing was bad before.

Changed:
- spark plugs (from bosh to original NGK)
- battery
- cleaned fuel system several times
- MAP
- filters
- timing belt (Fiat specialist did it, so should be fine)
- oil change with engine flush

Nothing helped. What helps: Switch from 95 octane to 98 octane.
With ONO (you will know from CZ) or other "cheap" 98 octane car runs just fine, every start from full tank to empty is fine.
100 octane (Verva/OMV/...) --> doesn't work, same problem
- also works - 1/2 tank cheap 95 and 1/2 Shell Vpower 100
- VIF aditiv doesn't work only with 95
- now I bought Millers oils petrol power ecomax - should add about 2 octane number to cheap 95 and I will test it.


I was asking for some ECU tuning/update, nobody in CZ was able to answer. Some cars here (same ae and engine specs) works fine, some has the same problem.

I also asked mechanic, if intermittent cold start could be problem for car (catalytic converter or lambdas, starte, idk...) but they said, it is only minor issue and it should not harm anything.

Also, mechanic said, that some 1.4 T-jet have issues with gas quality, so... seems legit.

Only problem is, that for example 100 octane is easier to find, and 95 is much cheaper, so I hope some kind of additive will help us, so we will be "free" to visit any gas station we find. In other case I will buy some 98 from ONO to jerrycans and I will pour it into 500 at home :D
Thanks for the suggestion, I will try some 98 octane fuel tomorrow, maybe the issue is the "biosložka" in the 95 octane fuel in CZ :D
 
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