Mismatched leak off from injectors on 2015 Audi TT TDi.

[MitchC]

Engine on my daughter’s TT will crank but not start. There are no fault codes, and it has had a new HPFP and FPR, along with timing belt kit and water pump. All lines and HP rail have been cleaned out, and pumped through using inline filters. Injectors haven’t yet been changed, but I think that’s coming. I don’t need lectures, just advice please.
Fuel system has been primed using VCDS, and it will run on easy start.
On cranking, 1&2 injectors have almost no leak off and 3&4 have fuel midway up the testing tubes. Would that stop all four injectors firing due to losing pressure through 3&4?

 

[Uwe]

On cranking, 1&2 injectors have almost no leak off and 3&4 have fuel midway up the testing tubes. Would that stop all four injectors firing due to losing pressure through 3&4?

On a TDI, yes, that's entirely possible.

Log requested and actual fuel pressure, and RPM, while cranking.

-Uwe-

 

[Dr Sheldon]

On cranking, 1&2 injectors have almost no leak off and 3&4 have fuel midway up the testing tubes. Would that stop all four injectors firing due to losing pressure through 3&4?

Does this have Piezo or Solenoid Injectors ? Is there a Valve in the Leak Off pipework ?

 

[Dr Sheldon]

and it has had a new HPFP and FPR,

Why ? Can we see the Diagnostic process and the measurements made that led to that decision please?

Source of replacement parts ?

 

[MitchC]

On a TDI, yes, that's entirely possible.

Log requested and actual fuel pressure, and RPM, while cranking.

-Uwe-

Done it, I’ll try and upload the video but think I’ll have to get an account of some sort.

 

[MitchC]

Why ? Can we see the Diagnostic process and the measurements made that led to that decision please?

Source of replacement parts ?

The car stopped while my daughter was driving it, possibly due to low fuel but she won’t admit it. I believe the HPFP decided to shit itself due to dwarf and I had low pressure on the scan I did. Before you ask, I don’t have the scan on my iPad so it won’t get posted tonight. I replaced it with a refurbished one and a new FPR.

 

[MitchC]

Does this have Piezo or Solenoid Injectors ? Is there a Valve in the Leak Off pipework ?

Pass, pass and no. The number on the injector is 041130277AE

 

[Dr Sheldon]

lets go again

Why ? Can we see the Diagnostic process and the measurements made that led to that decision please?

Source of replacement parts ?

Thank you !

 

[MitchC]

On a TDI, yes, that's entirely possible.

Log requested and actual fuel pressure, and RPM, while cranking.

-Uwe-

Not sure how to upload the video but try this

https://imgur.com/87YDzK8

 

[MitchC]

lets go again



Thank you !

Don’t take this the wrong way, but I’ve seen your posts on the Passat guy’s thread when I was researching this fault and I can’t be dealing with the way you spoke to him. I have no doubt you’re clued up to the eyeballs and have all the diagnostic equipment for the task but I just can’t be talked down to like that without retort.
I was down your neck of the woods in Windsor last weekend and if I’d asked you this in a pub in person, I’m pretty sure you’d have been more civil with your response.

 

[Dr Sheldon]

I’m pretty sure you’d have been more civil with your response.

Was I not civil the first time ?

Don’t take this the wrong way

Jog on !

 

[Dr Sheldon]

Oh dear
He wont tell me which sensor to change so I will go all Hero while me and my car is Zero cavalier !!

 

[Dr Sheldon]

What is the Reg No of your car ?

 

[MitchC]

You done?

 

[Dr Sheldon]

You done?

Done You

 

[Uwe]

Done it, I’ll try and upload the video

Making a video is not how one makes a log.

Watching your video though, it looks to me like the actual pressure is only about half the requested/specified..?

-Uwe-

 

[Dr Sheldon]

Making a video is not how one makes a log.

Watching your video though, it looks to me like the actual pressure is only about half the requested/specified..?

-Uwe-

A VCDS Graph would paint a better picture, Comparisons can be made to aid a better analysis into OP's woes.

Can we get one please ?

Here to help !

 

[MitchC]

Making a video is not how one makes a log.

Watching your video though, it looks to me like the actual pressure is only about half the requested/specified..?

-Uwe-

Apologies, I’m not fully clued up on how to make a log. I’ll have a search and give it a go. All I’ve done is post up scans before.

 

[MitchC]

A VCDS Graph would paint a better picture, Comparisons can be made to aid a better analysis into OP's woes.

Can we get one please ?

Here to help !

Thanks, and I’m not trying to be an arse. Can you tell me how to upload a VCDS graph please and I’ll do that, as I don’t think the scan would help because there are no faults showing.

 

[MitchC]

Making a video is not how one makes a log.

Watching your video though, it looks to me like the actual pressure is only about half the requested/specified..?

-Uwe-

Is it possible that the pressure is low because the 3 & 4 injectors are passing so much fuel?