Polo 6R CAYC Injector exchange

[BabaRoga]

Hello, First of all Im sorry for my bad english. I hope you dont mind.

Few days ago while I was driving my fuel injector died (cylinder no 3), I swaped injector with refubished one and programmed the new one with VCDS. Car started normally without any problems but changed injector was knocking louder than other injectors but it was ok to me.

While driving I noticed that car strugless at around 1200rpm so I knew that something is not right so I went to look at injection amount deviation.

Here is the result:



After that I started adaptation of injection amount deviation, but even after 20 minutes nothing happened. Car was running from 1000rpm to about 3500rpm endlessly so I decided to stop the adaptation because I found somewhere on forum that engines with dieselgate software cannot finish the adaptation.

After that I checked again for injection amount deviation for each cylinder and here is the result



this seems better to me but the thing is that car now runs roughly at 1000rpm and it behaves strangley engine shakes like it has epilepsy attack, it is loudly knocking and produces white smoke if you push throtle all the way down while it is at low revs. At 850rpm's it runs ok and also over 1500rpm seems to be fine.

So can anyone help me to solve this problem because Im stuck. Also can anyone check if I have dieselgate software running on my car or Im ok? I have VCDS, FVDI and FGtech so I can reflash it without problem if needed.

this might also be usefull



Im sorry about images but I got "forbidden. contains contacts" error message

[RUM4MO]

Hi, welcome to this forum!

If you do not get any or many good technical replies, maybe try another VW Group forum, I'm not sure that I have read any or much info on TDI engine technical issues in this section of this forum, and my wife's Polo has a petrol engine!

Skoda and SEAT forums seem to have more technical content, probably due to the "type" of person buying these brands of cars.

Maybe try www.briskoda.net and look/ask in the Fabia MK2 or MK3 sections, also www.seatcupra.net and look/ask in the Ibiza MK5 section.

Good Luck!

Also there might be forums dedicated to VW Group TDI engines and nothing else.

[amer6R]

Check id you entered correctly injector code. Im not 100% but it should start with 0 then the numbers od injector code.

[BabaRoga]

Thank you for replay. I did program new injector ID to ECU but Injector have 6 digit number and ecu accepted that except it added 0 at the end of code so injector code is: 73BBAD and I entered that as new injector value. When I read back value from ECU I got 73BBAD0.

Should I try program it to ecu as 073BBAD??

[amer6R]

Please try

[BabaRoga]

Toda< I tried as amer6R mentioned add 0 at the begining of code but ecu refused that. I got error message "Out of range"

[BabaRoga]

Just some update. Today I decided to remove all four injector, take them a part, clean them and tomorow i will test them on bench so that I can get new codes for all four injectors. Car was driven two days for about 120km in total and car performance did impove but still it hasitates at arround 1200rpm and fuel consumption is around 14L/100km (measured on dashboard).

I will post you tomorow with updates

[BabaRoga]

So I got results form test bench and it turns out that two injectors have fault electronics and two injectors didnt pass the test so i have four faulty injectors and I cant get new codes.

There is nothing left to do. I will buy for new injectors i monday ... I hope it will be fine

[amer6R]

You cold have also detirmined that by measuaring resistance on injectors via multimeter. Well its's sad, its not a small amount of money. The only good think is that you can can pull them and install new ones by your self. Fk simens and their s**t.

I have heard that the needle gets dirty and it wears out..

[gelotus]

Could I suggest to be more patient? Sometime the minimum quantity adapt lasts for over an hour.

[BabaRoga]

You cold have also detirmined that by measuaring resistance on injectors via multimeter. Well its's sad, its not a small amount of money. The only good think is that you can can pull them and install new ones by your self. Fk simens and their s**t.

I have heard that the needle gets dirty and it wears out..

Well thats why I was suprised.. I did measure resistance of each coil before testing on bench and they were arround 200k and 6uF each so that is not good indication as it seems. Also to mention first failed injector have resistance of only 10k and ecu did throw error message (check engine). Well yea siemens .... good thing is that I found injectors on aliexpress for arround 100€ piece with 6 months guarantee but I cannot wait one month for them to arrive, but i will order one just to have it if another injector fails. Bosh recplacement injectors cost more than double of that.

About dirty needles and wear I can say that I did clean all of them eight in fact. Four of mine and I did buy another four injectors from carambolized car fo cheap (250€) they were cleaned with ultrasonic cleaner filled up with paint solvent and they were all clean. I did notice some wear on them so ive chosen four sets wich looks the best and i did put them together before bech test. But because I didnt pair needle with nozle i think they failed the test because while assembling them i was looking for needle wich fits tightly in the nozle... I was thinking that if it fits tightly it will pass the test because needle were not worn out, but thats wrong because after testing report says that two injectors have too small back flow and other two wasnt tested at all because of bad electronics. So I assume that backflow is directly proportional to space beween needle and the nozle.

Could I suggest to be more patient? Sometime the minimum quantity adapt lasts for over an hour.

oooo I did run the test again this time I let it run for more that 3 hours. After arround 45 minutes of test, engine come to an idle for about 5 minutes but then it started again running from 1000rpm to about 3500rpm for another 45 minutes and then again idling for five minutes and so on...


Tomorow is another day. I hope that this storry will finish tomorow with new injectors. I did learned quite a bit about injectors last fiew days and I would like to learn more. Unfortunately im short with the money at the moment so I can not afford taking them a part again reassembling them and testing them again just to see how different needle, spring, rod and so on affects the test.

[BabaRoga]

Finaly the car is done

I bought 4 refubished injectors in locar car shop and I was supprised that they were refubished by VDO Newer the less after installing them and coding ive started the car and it happened again.. the car was hesitating at 1200rpm. You cannot imagine how I was feeling at that point. Ive repeated the injection amount deviation test and after 45 minutes car went to an idle. Ive stopped the test and I shut the car off. After starting it again it was the same .. again problem at arround 1200rpm.

I had nothing to lose so i did reset of all learned values, lambda, turbine, oxygen sensor etc.... after that car barely worked at the idle. Then I did run self test, they were no errors, then sequentional test and after that i started adaptation of everithyng I could. Lastly Ive started again injection amount deviation test. After another 45minutes car came to an idle and i turn it off again. After a minute or two I started car again and it worked as it should. no more hasitating at 1200rpm and performance seems to be better, like it have more power so luckily this storry have happy end. If nothing I hope that my horror story will help anyone who might searching internet for solution.

Never the less I appriciate any help I got here