OBDII : LONGFT1 -15% at idle ( Car running rich )

Will this situation ruin the catalytic converter and carbon up the engine in the long run ?
 
Can we make a list of things that should be checked on the car ?

1. Purge Valve
2. MAP Sensor
3. Oxygen Sensors ?
4. What else ?
 
0.7V on the upstream o2 is also reporting a rich condition. It’s trying to compensate by the -15% fuel trims you see. I would look at the engine, whether that be a MAP/MAF issue, or uncontrollable purge, excessive fuel pressure, a leaking fuel injector or a mechanical issue
 
So the list of things to check is :

1. Purge Valve
2. MAP Sensor
3. Oxygen Sensors
4. Fuel injectors
5. Fuel pump / Fuel Pressure Regulator
 
So what should the relation of OS211 and OS212 should be. What is considered ideal ?
In closed loop operation, the upstream sensor should alternate high and low fairly quickly. The downstream, once the catalytic converter is hot, should remain fairly stable unless you have fuel deceleration shutoff in which case it’ll go full lean (low voltage) when coasting.

Depending on your mileage, I’d say start with throwing some O2 sensors at it. At ~90k on my Dodge Caliber I started noticing really poor fuel economy not matter how nicely I drove, like 20mpg out of a 2 liter 4 cylinder. Never set any codes though, and all emissions system monitors were set. Replaced the upstream O2 sensor with a new NTK and my fuel economy immediately jumped up to a more reasonable ~25mpg.
 
In closed loop operation, the upstream sensor should alternate high and low fairly quickly. The downstream, once the catalytic converter is hot, should remain fairly stable unless you have fuel deceleration shutoff in which case it’ll go full lean (low voltage) when coasting.

Depending on your mileage, I’d say start with throwing some O2 sensors at it. At ~90k on my Dodge Caliber I started noticing really poor fuel economy not matter how nicely I drove, like 20mpg out of a 2 liter 4 cylinder. Never set any codes though, and all emissions system monitors were set. Replaced the upstream O2 sensor with a new NTK and my fuel economy immediately jumped up to a more reasonable ~25mpg.
The car is a 15 years old Daihatsu Sirion 1000cc with 60.000 miles on the clock.
 

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1. Purge valve is part of the emissions system and can be found in different places, but they have to connected to the intake or close by to the throttle body. So pick any line and follow it backwards to where it connects to a valve.

2. MAP sensor is connected to the intake in some cases very close to the throttle body

3. Fuel pressure regular close to or at fuel rail w/ vacuum hose and a return gas line to the tank
 
1. Purge valve is part of the emissions system and can be found in different places, but they have to connected to the intake or close by to the throttle body. So pick any line and follow it backwards to where it connects to a valve.

2. MAP sensor is connected to the intake in some cases very close to the throttle body

3. Fuel pressure regular close to or at fuel rail w/ vacuum hose and a return gas line to the tank
Can you find them on the schematics ?
 
Is my SPARKADV readings OK ? Could it be that I have bad ignition timing ?
 
I don't know ................. looking at all that has been said here I think there is simply too many unknowns mentioned.

I would suggest let the thing sit overnight and cool down completely.

Switch on ignition without starting the engine, and set up logging of the O2 sensor voltage.

Now start the engine and allow it to idle for about 2 minutes without touching the throttle at all.

Stop logging and lets have a look at the response/abilities of the ECU and O2 output logged there ..............

Also - is that an actual O2 or a wideband A/F sensor?
 
I don't know ................. looking at all that has been said here I think there is simply too many unknowns mentioned.

I would suggest let the thing sit overnight and cool down completely.

Switch on ignition without starting the engine, and set up logging of the O2 sensor voltage.

Now start the engine and allow it to idle for about 2 minutes without touching the throttle at all.

Stop logging and lets have a look at the response/abilities of the ECU and O2 output logged there ..............

Also - is that an actual O2 or a wideband A/F sensor?
Judging from the range or the reading my O2 Sensor seems to be narrow band.

My scan tool does not do logging or graphs. I guess I will have to take a video of the screen
 
You cannot draw that conclusion using the voltages only ...............

Narrow band or O2 will be producing a relatively fast changing voltage signal very close in form to a sine wave if all is well
 
Found a picture of the O2 Sensor and the plug has 4 pins from what I know this means narrow band
 

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