Technical Evap solenoid valve test

[VitSove]

Hello,

I´ve been trying to fix a flutuanting idle on a 2009 Fiat 500 1.2. Breather hoses were cracked and Map sensor covered in oil. Both replaced and throthle body cleaned. Now idle is stable unless You turn on full beam headlights. Then it goes up & down opening the butterfly on the throthle body and almost stalling. Spark plugs, cables and coil pack replaced. O2 sensor above cat also replaced.
I´ve read some topics here and now I want to test the evap solenoid valve. I disconected the blue pipe that comes from the fuel tank and it´s always closed, no vacuum, even with a full warm engine.
When does the evap valve opens? is there a way to test it further?

Hope someone can help.

BR,
Vitsove

 

[chris3234]

How old is your battery and what's the voltage like?

 

[VitSove]

How old is your battery and what's the voltage like?

Hi,
Thanks for Your reply. Battery is 6 months old and charging voltage is good. IT starts 1st time. Also checked and cleaned conections on the strap going from chassis to gearbox and they are good. We dont have salt here in PT... Full Timing kit fitted 2 months ago with locking tools and including thermostat. Problem was present before it was done. No fault codes and running really well except for this issue..
Next thing I wanted to check is the evap solenoid as I couldn´t see it open. When should it be open?

 

[VitSove]

Hi,

Update: Evap solenoid changed with a new one from autodoc. Its better but I can still ear the exhaust sound changing in an harmonic way when in idle and with lights on. Changed all the seals on the inlet manifold, no change. Yesterday swapped the injectors with 2nd hand ones, again its better but its still there. It doesn't stall anymore, now its an harmonic exhaust rumble if You turn on any big power consumption. Any thoughts on what to check next?

 

[VitSove]

Hi,
Forgot to mention i measured battery voltage using obd2 scaner.
In idle no electric load 13,8v to 13,9. Mostly 13.9 if it drops bellow 13.8 i start to ear the exhaust.
In idle with high load it drops to 12,9, 13,1,13,5 and this is what causes the fluctuation in idle every 2 to 3 seconds.

Should it drop so low? Alternator voltage regulator not doing its job? As I said battery is only a few months old

Any thoughts?

 

[VitSove]

Hi
Also tested with multimeter on battery poles:
Engine not running 12,85v
Idle no load 14,09v
Idle full load 13,9v drops to 13,3v and then up again every 2 to 3 seconds
At 3000 rpm 14,01v

Help anyone?

 

[VitSove]

Hi,
Since i saw a lot of topics without feedback for resolution here goes:
New throtle body, then, adaptive parameters reset, TB relearn followed by harmonic wheel relearn. Problem solved!
Idle is stable and engine performance was never so good!