VW Bora 2.0 8V AQY, vibration - Uneven engine operation, high fuel consumption.

Hello,

I bought Bore 2.0 8V with BRC gas. I have read a lot of topics but I have not found most of the answers to my questions.
Symptoms:

- large combustion 17-18 liters / 100km
- uneven engine operation (rpm does not wave on the clock, but shakes it like jelly)
- very light shots from the pipe
- under engine firing to comp. shows the consumption of 50l / 100km and it decreases a bit. I read that the reason for such combustion can be a spent catalyst?

When connected to a computer, it showed errors:

- ignition on 2 and 4 ignition
- lambda probe (I did not pay attention to it at that time)

After checking the cable plugs etc, I decided to replace the coil. This is how the new art of Beru happened.
It was even ok only after traveling ~ 150km of vibration, high combustion returned.
So again connecting to the computer and we have the following errors:

16518 Lambda Sensor no voltage change (Page 1 sensor 1)
17536 Mixture too poor page 1 long-term regulation - sporadic error

Ignition loss is gone.

After recent tests, I noticed that driving on gasoline, there are no errors at all. After switching to gas and after driving a few km, error 16518 will appear, but the car will still work nicely, in a few days, it will start to jerk again (unless the check lights up early and error 17536 pops up, it is immediately a change for the worse)

Yesterday I noticed that the counter shows me a temperature of 90 degrees, but after connecting the computer, it shows over 100 on vag and it increases. In this case, focus more on the temperature sensor or thermostat?

Someone has already fought such a case?

Check if the probe works properly on PB. If so, what does it show on LPG.
After deleting the settings learned in channel 00 in adaptations in the engine it should work better on PB.
You have the LPG set incorrectly or the LPG lambda probe does not work and the petrol map in the engine controller is running down, which causes these problems.

The probe works properly, after deleting errors or disconnecting the battery problems immediately disappear but not permanently

It's a few days, don't use gas, check 100% if it's not what he wrote grala1 because you probably didn't understand his statement.

heniek1821 wrote:

Yesterday I noticed that the counter shows me a temperature of 90 degrees, but after connecting the computer, it shows over 100 on vag and it increases.

Do you have two sensors in one housing? You had to feel the radiator and hoses then, are they not getting noticeably cooler because the fan was working?

There, the counter will show 90 on the counter as the engine temperature will be in the range of about 70 to 105 degrees.
There are two sensors in one housing, so you should compare the meter reading with the ECU reading.
It is worth checking if the first gear of fans works because quite often the first gear resistors sit down and the temperature goes up.
After switching on the air conditioning, both fans in first gear are to start immediately. If they move, you can check the thermal switch on the radiator and simulate its operation - make a jumper for 1st and 2nd gear.

Since the errors disappear after unplugging the battery, the map in the petrol controller disperses. LPG or probe not set correctly.
In the measuring blocks in the engine you will see how it increases in plus dose enrichment because it sees a lean mixture or no probe response to LPG.

Gentlemen, yesterday I connected Vag again and it weakened me ...:

16518 Lambda probe no voltage change (page 1 sensor 1) no accessories / not related to the equipment
16684 Random ignition loss no accessories / not related to hardware - sporadic error
16686 No ignition cylinder 2 no hardware / not related to equipment sporadic error

I already thought that after changing the coil, I have a problem with the loss of ignition because I haven't had this error for a long time.

Did you change cables and spark plugs?
What do you mean by writing

heniek1821 wrote:

After checking the cable plugs

How's the gas installation? What components of it?
Did you follow the advice of your colleagues and did you only go to PB for some time?

I checked the cables by spraying water at night, there was only a small, hardly visible sparks, the unscrewed candles also look ok.
BRC installation. After clearing the error from yesterday the car drives normally without any faults but of course until. I drove the PB test for 20km on gas the probe appeared (when connected to the vag because the check is lit only after a few days driving when the error appears with a poor mixture), while there is no error on the PB.

You have incorrectly adjusted LPG or the reducer is not making.
It is necessary to check whether the regulator maintains the set pressure and how to adjust the installation.

At what mileage did you buy the car and how much had it "gone" on gas, did the previous owner do anything in the installation. Because from what you write, adequate regulation should suffice, but as e.g. the gas mileage is much greater than 100,000 km, perhaps regeneration of the reducer would also be useful.

I wonder if according to the previous owner properly serviced it and whether according to serviced. BRC is a good installation, it is good not to blame the matter at first and set the service as an adjustment. If lambda has errors, I bet on a poor mixture and maybe the lpg regulation alone is enough.

Hello,
I come back to the topic after a long break. After cleaning the gas injector (infiltration of the cleaning agent) there was improvement for some time, the jerking stopped, but the combustion, probe error and rattling from the pipe still remained. The day before yesterday, the problem with jerks came back and the errors were joined by a random ignition failure + ignition loss on the second cylinder. Yesterday I went to a decent gas burner who took out my gas injection rail for washing in an ultrasonic bath and cleared the errors. Returning home on the PB there was no jerking, burning on the road at the level of 13.5 l. After driving 50km I set up to connect the computer and check what is going on (although the check did not pop up). And I saw errors of course the probe: 16518, 16521, 17536. I don't know whether to change the probe or not? The incorrect result of the probe can also be influenced by the flow and the damper. How to exclude their failure?

It is possible that the reducer fails and the LPG map is worth a look. Go to some BRC magician.

Well, today, they will check everything for me as they will mount the strip after washing, but here is the problem that on the PB itself at the longer route crashes for me these probe errors. The question now is how to check whether the flow or damper does not cause these errors

If you have cleared errors before and after driving on PB shows no voltage changes on the probe, I would rather suspect a damaged probe, unless it is mega poor.
Show what the probe shows at idle and when booting, the same with the flow meter.