Just had injectors recoded at VW AUDI specialist and instead of lumpy idle I now have diesel knock. Anyone tried liqui moly diesel purge with any success? 1.6 terrible damn idea.

2 hours ago, JPW2010 said:

Just had injectors recoded at VW AUDI specialist and instead of lumpy idle I now have diesel knock. Anyone tried liqui moly diesel purge with any success? 1.6 terrible damn idea.

 

Snake oil is NEVER the correct answer.

4 hours ago, JPW2010 said:

Just had injectors recoded at VW AUDI specialist and instead of lumpy idle I now have diesel knock. Anyone tried liqui moly diesel purge with any success? 1.6 terrible damn idea.

 

1 hour ago, sepulchrave said:

 

Snake oil is NEVER the correct answer.

Which particular snake oil is that?

6 hours ago, JPW2010 said:

Just had injectors recoded at VW AUDI specialist and instead of lumpy idle I now have diesel knock. Anyone tried liqui moly diesel purge with any success? 1.6 terrible damn idea.

Hi Mate have they put in the correct injector codes when they were recoding it and have you put in brand new injectors or second hand the injector you have put in might be faulty 

 Based on previous post where it was just a shudder, is this with the old injectors being re-coded, or with the new injectors they suggested that you needed. If the old injectors may be worth either getting them to try a re-code again, or visiting another garage who may re-code differently as new injectors will be costly.

The judder got progressively worse. Bought the car in late January with no obvious juddering but after a few cross country drives the judder became pronounced and turned into the point where the entire engine was shaking on idle. Original injectors recoded by a VW Audi Bosch specialist (so they say). Asked about driving to Cardiff and Leicester from north west Wales and he said he doesn't recommend it. Paid £120 for the diagnostic and recoding. He said he couldn't put them back to how it was before but I wouldn't want it like that either. 

14 hours ago, thomasaspin said:

Hi Mate have they put in the correct injector codes when they were recoding it and have you put in brand new injectors or second hand the injector you have put in might be faulty 

I Don know about the coding but they are the original injectors. I hope they put the correct codes in. Sounds like a tin of nails.

19 hours ago, KenONeill said:

Which particular snake oil is that?

 

For this particular application, Rattlesnake oil...

Each injector has a compensation code on them and they need to be coded correctly or will run like complete crap 

Spoiler

 

Spoiler

not sure what spoiler is but car is knackered at the moment - sounds like a washing machine with nails in and blowing white smoke. No poke. Anyone got a diagram of intercooler pipes/vacuum pipe turbo location? Taking it back for re-diagnostic at the request of Bosch specialist.

 

Good, the job obviously wasn't done right...

Having a hard time getting the 'specialist' to admit fault. It was perfectly fine with slight pressure on the accelerator (still well below 1000rpm) and I was getting 70mpg +|-. Now i can't even drive it to the garage to get another diagnostic. 

29 minutes ago, JPW2010 said:

Having a hard time getting the 'specialist' to admit fault. It was perfectly fine with slight pressure on the accelerator (still well below 1000rpm) and I was getting 70mpg +|-. Now i can't even drive it to the garage to get another diagnostic. 

 

You won't get them to admit fault, just ask them to put it back the way it was using the original injector adaptation values.

You may want to try and find someone local with VCDS - there is a listing somewhere on here - who can scan the car to give a full report on any issues. Dependant on their experience using the programme, they may even be able to read the injector values and adjust to the required if there appears to be an issue.

 The fact that they say they cannot put back to the original values may suggest they did not record these values. What sort of specialists are these - VW/Audi or Bosch fuel injection.

Edited 1 May, 20224 yr by KeithCheetham
Specialists at what

50 minutes ago, JPW2010 said:

Having a hard time getting the 'specialist' to admit fault.

As @KeithCheetham suggests, you don't actually need a VAG specialist here; any Bosch Diesel or TurnerTune shop will do the needful.

2 hours ago, KenONeill said:

As @KeithCheetham suggests, you don't actually need a VAG specialist here; any Bosch Diesel or TurnerTune shop will do the needful.

I think that a scan on VCDS is needed 1st to ascertain any underlying issues that may have pre-existed - faulty injector wiring etc, as while the "specialist" has changed one issue into another (worse one) it may be possible for someone with the necessary VCDS experience to set the coding to that actually relevant to the injectors then at least the OP would have a system at the original baseline/configuration. I am also unsure if the "specialist" has changed an issue on 1 injector to an issue with all 4 injectors. This is why I questioned the base trade of this specialist - are they a VAG specialist who "dabbles" with fuel injection, or a fuel injection specialist.

36 minutes ago, KeithCheetham said:

I think that a scan on VCDS is needed 1st to ascertain any underlying issues that may have pre-existed - faulty injector wiring etc, as while the "specialist" has changed one issue into another (worse one) it may be possible for someone with the necessary VCDS experience to set the coding to that actually relevant to the injectors then at least the OP would have a system at the original baseline/configuration. I am also unsure if the "specialist" has changed an issue on 1 injector to an issue with all 4 injectors. This is why I questioned the base trade of this specialist - are they a VAG specialist who "dabbles" with fuel injection, or a fuel injection specialist.

It's a VW AUDI PORSCHE specialist with Bosch accreditation. Seems pretty clueless about what he's done as he's admitted they altered/re-set the codes based on their previous experience of the fault being caused by injectors on different cars.

Didn't even show up on the diagnostic report. Also suggested it APPEARS to have got worse since they changed the codes. 

Hello John

As I said on the phone I am sorry you have a running problem with your 
car and that it got worse after we had re-entered the injector codes as 
part of the diagnostic 

During diagnosis we scanned the fault codes there was an old code for 
fuel pressure, this cleared and did not return even after a road test.

As we have seen unstable idle faults before often due to injector coding 
having been 'lost" by the Engine Control Unit ECU we then re-introduced 
the codes physically written on  injectors (which were the same as the 
codes previously stored in the ECU) back into the ECU via the computer, 
after doing this the idle was stable. However during road test it 
appears that a more pronounced diesel knock became apparent.

We then advised you that the fault was almost certainly with the 
injectors. As genuine Skoda Injectors are over £500 each we would need 
to send the injectors away to be tested and if necessary.

I can appreciate that your car appears to have got worse after we worked 
on it, however there is nothing we physically did to cause this and my 
view is still that the defect was potentially there already.

I have already offered as part of our complaint procedure to investigate 
further without additional charge, this in line with the Bosch code of 
conduct as approved by Trading Standards.

Yours Tim B.

7 hours ago, JPW2010 said:

Hello John

As I said on the phone I am sorry you have a running problem with your 
car and that it got worse after we had re-entered the injector codes as 
part of the diagnostic 

During diagnosis we scanned the fault codes there was an old code for 
fuel pressure, this cleared and did not return even after a road test.

As we have seen unstable idle faults before often due to injector coding 
having been 'lost" by the Engine Control Unit ECU we then re-introduced 
the codes physically written on  injectors (which were the same as the 
codes previously stored in the ECU) back into the ECU via the computer, 
after doing this the idle was stable. However during road test it 
appears that a more pronounced diesel knock became apparent.

We then advised you that the fault was almost certainly with the 
injectors. As genuine Skoda Injectors are over £500 each we would need 
to send the injectors away to be tested and if necessary.

I can appreciate that your car appears to have got worse after we worked 
on it, however there is nothing we physically did to cause this and my 
view is still that the defect was potentially there already.

I have already offered as part of our complaint procedure to investigate 
further without additional charge, this in line with the Bosch code of 
conduct as approved by Trading Standards.

Yours Tim B.

They can bring up live data of each injector if one is stuck open over fuelling or vice versa it will show which injector is faulty and you will only have to replace one , I had diesel knock once and it was due to an injector stuck open 

As thomasaspin has put a higher level scan tool gives so much information that someone that really understands the information has a really good base to start diagnostics from.  Viewing live and recorded data should give lots more useful information that can be interrogated and interpreted but it can require time to do this properly - and a person able and willing, or allowed to.

 

As  - "re-introduced the codes physically written on  injectors (which were the same as the codes previously stored in the ECU) back into the ECU via the computer" I'd want to see that information as I very well know about typos, it will be on their computer but you might  (ETA: not) be shown it - but again a mismatch should show up in its performance anyway on subsequent runs of the scan tool.

 

"As genuine Skoda Injectors are over £500 each we would need to send the injectors away to be tested and if necessary." - And if necessary what(?).

 

Unfortunately you are stuck in their complaint procedure and if you try to break from it you very much risk losing whatever the cost of their work is if you take your car elsewhere for repair.

 

Everyone makes mistakes, if they've made a mistake it's up to you if you trust them to rectify it and put your car right.  Personally from much bitter experience of the car trade I'd forget any admission of mistakes on their part and consider not putting good money after bad with them if you don't trust them and write-off your loss with them and move on but only you know how you feel about that.

 

Edited 5 May, 20224 yr by nta16
forgot the 'not'

23 hours ago, JPW2010 said:

Hello John

As I said on the phone I am sorry you have a running problem with your 
car and that it got worse after we had re-entered the injector codes as 
part of the diagnostic 

During diagnosis we scanned the fault codes there was an old code for 
fuel pressure, this cleared and did not return even after a road test.

As we have seen unstable idle faults before often due to injector coding 
having been 'lost" by the Engine Control Unit ECU we then re-introduced 
the codes physically written on  injectors (which were the same as the 
codes previously stored in the ECU) back into the ECU via the computer, 
after doing this the idle was stable. However during road test it 
appears that a more pronounced diesel knock became apparent.

We then advised you that the fault was almost certainly with the 
injectors. As genuine Skoda Injectors are over £500 each we would need 
to send the injectors away to be tested and if necessary.

I can appreciate that your car appears to have got worse after we worked 
on it, however there is nothing we physically did to cause this and my 
view is still that the defect was potentially there already.

I have already offered as part of our complaint procedure to investigate 
further without additional charge, this in line with the Bosch code of 
conduct as approved by Trading Standards.

Yours Tim B.

They aren’t over £500 🤣