Technical Panda 169 New Throttle Body question

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Technical Panda 169 New Throttle Body question

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Greetings everyone, this will be a bit complicated explanation.

-Previous fault lamp, irregular operation, stalling.
I had problems.
I determined that the map and eccentric cable were broken and repaired them.

-I detected some vacuum leaks. I fixed it.


Despite these, I thought my idling was not very good. I don't trust iacv very much. When I disassembled it before to clean it, the plastic came off easily. It has worn out over the years.


-While I was investigating the first malfunction above, I also purchased the throttle body.


Now I decided to assemble it.

After installing it, the idling performance of the car increased significantly.
The vehicle started to reach idle speed much more easily and quickly.So yes, my problem was here and it was fixed. I experienced very positive developments. The time I have to wait for the car to idle while stopping, starting and maneuvering has decreased.



Problem;


  • I guess he didn't recognize the new throttle body correctly.
  • Sometimes the idle remains constant at 1400 rpm. (Too high) (I'm not talking about the automatic choke procedure)
  • In general, it stays healthy at 800 rpm.
  • Sometimes it is wavy like 800-500 -800-500rpm. It works.

But despite its choppy operation, it never knocks or tends to stall. So my vacuum circuit is very healthy.


The LPG circuit is a retrofitted circuit. When running on LPG, the rpm is currently around 1500. I need to go to the service to set this up. But the problems I am talking about now are the events that occur when the LPG system is turned off and the vehicle is started on gasoline.​


Question;

  • Is there any automatic identification procedure that I know of? Or is there?
-Remove the terminal - Reconnect after the new throttle body. (20 minutes no energy)
  • Also, when I disassembled the old TB, I observed that it was quite oily. There may be too much oil coming from the vapor recovery pipe.




Fiat panda 169  1.2 motor 8valf Gaz kelebeği seti değişimi  (5).jpg
 
The fueling is a feedback loop from the O2 sensor

Any adjustments are stored in

Short Term Fuel Trim STFT
Long Term Fuel Trim LTFT

At idle the LTFT should steady and near 0

If any cylinder is not firing, the LTFT will be way positive

If it's not way positive we can assume that the cylinder are all firing okay and we can move on

LTFT is a missing value from MES so its good for use here

I never tried it but something like VCDS should work

I use torque but it's not working on your car
 
I lost the locking ring of the throttle cable.
I tightened the hose clamp for now.

Does anyone have any advice on what I can do about this?



Also for idling.
I ordered spark plug cables. Bosch brand.
I will proceed with small experiments.
 

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When the alternator gets a load of 10-20 amps or more, the idle definitely improves.

When I turn the flashlight while the dipped beam headlights are on, it gets better.

I started reading alternator topics on the forum.
Even when the car is idling, my voltage is around 13.8volts. I didn't measure the amperage, but I'm 100% sure the alternator is producing enough electricity.


I want to check the alternator.

what's on my mind

-Removing the alternator energy transfer socket, if any, and disabling the charging process in the car

- Testing by connecting an external high battery charger.

-Checking under the alternator with an endoscope camera.


My vehicle was used in a city that was exposed to a lot of cold and a lot of heat.
(+45° in summer - 25° in winter) Therefore, whenever I disassemble a part, I have to replace the rubber o-ring or plastic part.

Could this misfortune have also hit the alternator?


Fuel terms and spark plug control are in my mind.

I couldn't use the car much. I will take it apart soon and check the spark plug colors.

And I will install new spark plug wires (bosch brand)
 
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I installed new spark plug wires.
I had new spark plugs installed 100 km ago. I have been using the vehicle on gasoline for 100 km. Spark plugs are as seen in the photo, all are healthy and equal.

I just installed the spark plug wires. The 100 km test was done with old cables.

Test 2

I started the car from the power source. I did a test to ensure less load on the alternator. Nothing has changed.
I did the visual integrity check of the alternator with an endoscope camera. stable.

The idle problem is less common these days. I attribute this to the cold weather.

I don't know what's next.
 

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There's an adjustment screw on the throttle body? Have you made any adjustment to the throttle stop via this screw? There should be no tension on the throttle cable with the accelerator pedal depressed.
 
There's an adjustment screw on the throttle body? Have you made any adjustment to the throttle stop via this screw? There should be no tension on the throttle cable with the accelerator pedal depressed.

Please don't touch the screw it's set at the factory, Once set it never needs touching, there is no way to reset it properly and just adds another unknown variable

Cable operated throttle bodies idle is controlled by the idle control valve

Actual rpm is read by the Crank sensor

The desiresed rpm is set by ECU

And controlled by the ICV

Pulsing revs is due to the engine nearly stalling and the ICV opening up to prevent it
 
Hello. There is no tension in the throttle cables. The adjustment screw has never been tampered with. It is original. I have information that it should not be played. thanks :)

The colors of the spark plugs are now even and healthy.

The malfunction occurs especially when the vehicle approaches 95 degrees to turn on the fan.

-Faults occur more frequently in LPG.

Malfunctions occur more frequently on LPG, regardless of temperature.

-Faults occurring in gasoline become more controllable. The vehicle is less affected by the problem. Also, when I press the pedal, the problem disappears.


One question;
When I turn on all electrical loads (glass resistor, heater fan, high and low beam) while the vehicle is idling
The intake manifold value increases to approximately 440mpa. (Idle)
Is this situation considered normal?


What could be the malfunctions that occur more in LPG and less in gasoline?


The car's first malfunction was a burst water pipe and overheating.

Could the valves be damaged?
Would the spark plugs have a healthy color if the valves were damaged?
 
In your message. After doing a little research, I better understood the importance of ltft and stft values.

I ordered the oxygen sensor removal socket.

First, I want to disassemble and clean the sensors. In the meantime, I will try to connect to the vehicle again with programs such as Torque.


I saw some serious warping under the manifold. Approximately 2 fingers caved in.
Would this be a problem?
 

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In your message. After doing a little research, I better understood the importance of ltft and stft values.

I ordered the oxygen sensor removal socket.

First, I want to disassemble and clean the sensors. In the meantime, I will try to connect to the vehicle again with programs such as Torque.


I saw some serious warping under the manifold. Approximately 2 fingers caved in.
Would this be a problem?

Fairly typical bump and bash

I use to bash mine several times a year on farm tracks

If the front wheels go down a dip there's no clearance here

Is unlikely to be causing a problem, there's no guarantee but mine are much worse

LTFT at idle would tell us if the ECU is needing to add or taking away fuel from the standard map, If is around the centre mark we would know everything is as it should be combustion wise and we can move on to the idle control side

These are the only part numbers I could find



I don't think the bit you want is sold seperatly
 
@atakan123123 , just a quick post to say that I am following this thread very closely as I am experiencing very similar symptoms to you.

My car is a Fiat Panda 2009 1.2 petrol and my idle is erratic. Sometimes it is fine, sometimes it holds higher (1,200 RPM or 1,400 RPM – at the expected set points) and sometimes it fluctuates/cycles between 500 and 1,200 RPM. This is most notable when the engine is warm.

Increasing the electrical load often causes it to quickly hop back to the expected warm idle (around 800 RPM) and it holds well, e.g., turning on main headlights. If I then pump the accelerator it may settle back to an elevated setpoint or fluctuate.

I do not have a solution for this. I have tried a number of things that made no difference for me: spark plugs, ignition leads, throttle body, vacuum leak testing, throttle position signal measurement, lambda sensors, … Nothing made any difference. The car runs great generally but the varying idle is a pain.

In case it may be useful check out my post here: https://www.fiatforum.com/threads/bad-idle-judder-and-brake-revving.498455/
I resolved all of my issues with the exception of this erratic idle.

Also I don't want to derail your thread so if anyone has feedback please leave it on my original post linked above unless it is relevant to @atakan123123 also.

My current thinking is that something is slightly off in the control loop and I am going to revisit with my old (but OEM) lambda sensors. If I ever resolve this I will let you know.
 
There isn't one answer

I have had hunting and stalling due to a blown head gasket

@jasimog has had a idle control Valve and is going to post the normal settings


And here's one that probably a leaking inlet manifold


Plus many more

Which is why you have to gather as much information as possible

For example my head gasket was easy to diagnose as the long term fuel trims go very positive at idle and reduce when the revs are raised to 2K
 
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Which is why you have to gather as much information as possible


For example my head gasket was easy to diagnose as the long term fuel trims go very positive at idle and reduce when the revs are raised to 2K
Did I understand correctly? Did you understand the gasket condition by looking at the fuel trims?

Meanwhile, most parts of the ignition system have changed.
Spark plug cable, spark plug and ignition coil were replaced.
spark plugs are ngk brand.
The coil and cable are Bosch brand.

Currently, there are almost no malfunctions in gasoline. I don't remember the last time I had a rough idle.

I don't think it's better because of the new parts I installed.

LPG also starts to malfunction immediately. I wonder if my problem has been solved?

but it makes a mistake because it uses the LPG historical fuel map. As a result, it creates the map by taking reference from the gasoline map.



Things I still haven't done;

-Oxygen sensor cleaning
-Injector cleaning

I have these in mind.


I can't access Ltft stft values.


Torque not working. I also tried some computer programs. Like "obdwiz".

Only "mes"i software can be connected to the vehicle. I'm wondering what makes the "Mes" program different from others? Why can he connect while others cannot?
 

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Each misfire sends a slug of unburnt air down the exhaust,

The O2 sensor mistake this as a lean condition, and will max out fuel trims

LTFT will identify a misfire but not what causes it

On the software I use 1 cylinder misfire at idle is around +50 and a 2 cylinders around +99

So if the LTFT are plus +99 at idle and this falls but still very positive at 2000 RPM I know it's likely to be a cylinder head and this is the direction I would go with further testing
 
I removed the oxygen sensors.

It looks pretty clean.
Only the top one changed color because it was exposed to more heat.

I cleaned both with brake spray.

Since the lower and upper sensor codes are the same, I changed their positions.
The upper one is connected to the lower one. The bottom one got stuck on top.

Of course, nothing has changed in the vehicle :)

I know it won't be a solution, but I will also remove the fuel injectors and clean them.

I still can't see the Ltft Values.
I wonder if it would help if I buy an "afr meter"?


In the video, it can be seen that it runs very well on gasoline and has very few and rare idling problems. Nowadays, idling problems are very rare with gasoline.


It immediately starts to cause problems when working with LPG.


A friend of mine has a smoke leak detector. I will test it again for leaks when I borrow it.
 

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My last test is the injector test.
I benefited from the "Mes" program.
They all seem to pump fuel at the same rate. It is strong enough to hit my hand from a distance of approximately 70 cm.

All 4 injectors are the same.

They look quite healthy.

I still cannot reach the Ltft, stft values. My work ends here for now.
 

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Good update

It is not really possible to clean a lambda sensor.

Good practise is not put any part of your body in path of injector spray. Diesel injectors and direct injection petrol injectors would probably lead to having an amputation of hand or arm etc
 
...but why are you testing the fulinjectors when you say the problem is worse on LPG?
Just a thought: do the fuel injectors switch off completely when set on LPG?

gr J

hi , The information I received when I contacted LPG services is as follows. Even a 5% error that may occur in gasoline use is more reflected in LPG.
(Because LPG has lower flammability than gasoline.)

On the websites of all LPG services, they write about LPG settings or malfunctions: Before arriving, make sure that your vehicle runs properly on gasoline.

In the LPG mechanism, fuel is first controlled in the solenoid. It is then controlled by the injector. Even if one is faulty, the other must be intact. It passes through 2 separate levels.

I checked the integrity of the solenoid and injector. No gas flow when not activated.


I checked the fuel injectors because they may be leaking or spraying less.
 
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