Hello,

I own a Stilo 1.6 16v 11/2001 about 90.000miles and I got some troubles with it.
When it's at low rpm (about 90 degrees temp) at 700-800 rpm sometimes it gets lower and the car is trembling.

When that happens, either I accelerate it or I open the AC it gets to around 1000rpm and everything is cool.

I attached the Fiat ECU Scan small diag log here as I couldn't attach the CSV file...

READ PARAMETERS:
Engine load: 15.250 Kg/h
Spark advance: 2.3 deg.
Baro pressure: 998 mBar
Injection time: 4.418 ms
Throttle position: 4.8 deg.
Misfires (2): OK
Lambda signal 1 (Pre-Cat.): Closed Loop
Engine temperature: 69 °C
Air temperature: 39 °C
Manifold pressure: 445 mBar
Engine speed: 842 rpm
Lambda 1 status (After-Cat.): System lean
Lamda signal 1 (After-Cat.): Open Loop
Desired idle RPM: 831 rpm
Evaporation control valve opening: 3.8 %
Cylinder 1 timing: 0.0 deg.
Cylinder 2 timing: 0.0 deg.
Cylinder 3 timing: 0.0 deg.
Cylinder 4 timing: 0.0 deg.
Mixture correction learning value: 1.031225 %
Lambda sensor 1 integrator: 1.091050 %
After-Cat. lambda sensor signal: 0.175 V
Pre-Cat. Lambda sensor signal: 0.336 V
Lambda 1 status (Pre-Cat.): System lean
Lambda sensor 2 integrator: 1.026450 %
Knock sensor signal Cyl. 1: 0.717 V
Knock sensor signal Cyl. 2: 1.235 V
Knock sensor signal Cyl. 3: 0.732 V
Knock sensor signal Cyl. 4: 0.839 V
Coil 1 charge time: 1.804 ms
Coil 2 charge time: 1.550 ms
Coil 3 charge time: 1.550 ms
Coil 4 charge time: 1.550 ms
Air pressure (calculated): 511 mBar
Throttle angle: 0.0 %

did you clean your throttle body?
i notice a weird difference for knock sensor signal cyl. 2 and coil 1 charge time - normally these values are rather close together for the different cylinders....

Hello,

I haven't cleaned the throttle body yet (I was thinking about that aswell) will do it soon at some good service around. SInce I'm from Romania and here we got few good mechanics.

The wierd difference I've noticed myself too, that's why I focused on these on the log. What that might be? What does that mean? Is has any association with the coils and the spark plugs?


Also, what about these?
Coil 1 charge time: 1.804 ms
Coil 2 charge time: 1.550 ms
Coil 3 charge time: 1.550 ms
Coil 4 charge time: 1.550 ms

Thank you!

start with the throttle body cleaning and check if your coil nr. 1 is a different brand - this might explain the difference in charge time.
You might also put a bottle of injector cleaner in a full tank and refill at half full to clean your injection system.
Did you read any fault codes?

Hey, sorry for the delay.

No, no fault codes yet. Hope never will get
I will try to clean the throttle body at some service... can it be cleaned by myself?

Sorry to bother,
I seem to have another issue right now.
When accelerating, sometimes it gives a misfire or discontinues for a milisecond, like it has some garbage in the petrol

I gave a ride with the FiatECUScan working and when that misfire or whatever it is happens, the Cylinder 1 Timing is more than 0. It ALSO WAS 6551.8 or 6553.4 !!

The normal values of it are 0, 0,5, 0,1...etc.

Can you tell me what is that cylinder and what could the causes be?

Thanks!

Ok, the problem with that cyclinder timing was a ignition coil. I've changed it and there are no misfires anymore..
But there still is the trembling at low rpm, it goes from ~900 to ~600rpm and goes back and goes like that until the car dies. Sometimes when I am in traffic and I reach the stop line and I get the gearbox on free, the car dies.

This last part happens since I've changed the distribution.
Could the timing be wrong? I mean, if some teeth are displaced..?


Thanks..

i did not read anywhere you cleaned the throttle body in the meanwhile - that's the first thing to try now...
Fitting new spark plugs often improves the behaviour of the engine - that's worth a try too.....