1.6 TDI high tickover and smoking

[Mulberrry VR6]

Hi all,

Hoping one or some of you can help as I have reached the end with my Mk6 variant 1.6tdi, I have spent a small fortune on diagnostics and parts trying to fix this issue and it still is not resolved.

A bit of background, I have owned the golf for around 3 years now and I have covered 40k miles and I am regularly doing long distances.

Issues

• Constant tick over at 975rpm even after a long run.
• Fans on after driving.
• Black/Grey/Blue smoke when cornering (Left hand down).
• Over powering smell of diesel in cabin.
• Poor MPG
• High oil dilution
• Particle filter measured soot mass at negative 126g

Levels.jpg

Diagnosis

• EGR working correctly
• Failed injector
• Possible failing particle filter
• Leaking exhaust clamp

Works carried out

• New Injector (seals etc)
• EGR Full Clean and then EGR blank. blank now removed again as thought it might have caused the issue).
• All readings on DPF are low.
• Full service every possible filter
• New particle filter sensor
• Full carbon clean
• New pre DPF 02 sensor

The car is becoming unusable due to the diesel / oil dilution and the fact that the diesel fumes coming through the air vents is so over powering.

[mickeybo]

Can you post up your reg no or engine code

[Roverfan]

Picture inside of tailpipe should reveal if dpf is working. Should not be getting black smoke with a dpf equipped vehicle

Also when did the problems start and if the emissions recall has been carried out and when. This is to rule out constant regen attempts after map being taken back to stock after a previous dpf delete map with a gutted dpf.

[Crasher]

The engine code will be a CAY, either the B or most Common C. These engines have been an absolute disaster since day 1 and was THE engine at the centre of the VW emissions fiasco. They suffer terrible problems with their DPF (It is clearly fighting to regenerate), EGR and injectors, the latter alone cost £2500 alone to replace using VDO aftermarket and more genuine VW at £3084.86 for the four injectors alone. I can’t tell from the replaced list if the injectors are new.

Can you post a code read of the engine management as it is now?

[Mulberrry VR6]

All,

Thanks so much for replying.

Here are the answers to the questions you asked.

1. Can you post up your reg no or engine code
      
Engine Code is CAYC


2. Picture inside of tailpipe should reveal if DPF is working. Should not be getting black smoke with a DPF equipped vehicle


Exhaust.jpg 


3. Also, when did the problems start and if the emissions recall has been carried out and when. This is to rule out constant regen attempts after map being taken back to stock  after a previous DPF delete map with a gutted DPF.


The issue started around October 2023, from what I am aware there are no recalls outstanding.


4. The engine code will be a CAY, either the B or most Common C. These engines have been an absolute disaster since day 1 and was THE engine at the centre of the VW    emissions fiasco. They suffer terrible problems with their DPF (It is clearly fighting to regenerate), EGR and injectors, the latter alone cost £2500 alone to replace using VDO aftermarket and more genuine VW at £3084.86 for the four injectors alone. I can’t tell from the replaced list if the injectors are new.


Can you post a code read of the engine management as it is now?


There are no codes showing from any part of the car.

-----------------------------------


Question - What sensor does the ECU get the Particle Filter Measured Soot Mass reading from as a reading of -126 cannot be right or can i need to get the parameters reset to zero?

[Roverfan]

The tailpipe shows a good working dpf (soot particles are not passing). You did mention the leaking exhaust clamp and I'd look at that and other spots to ensure the pre dpf exhaust system is sealed. Similar regen issues have been reported due to leaks. The metal gaskets are often smeared with grease which hardens but on refitting this needs to be cleaned as it's too hard a substance to aid resealing if slightly mislocated from original spot. If the smell you detect is coming from the engine bay then there is a leak.

The dpf pressure readings come from dpf pressure sensor (via a small tube from dpf housing) and can read minus but I've not come across such a low reading before. Hopefully it will be a leak causing the low reading but check to see if pipe and hoses to dpf pressure sensor are not blocked

[Mulberrry VR6]

The tailpipe shows a good working dpf (soot particles are not passing). You did mention the leaking exhaust clamp and I'd look at that and other spots to ensure the pre dpf exhaust system is sealed. Similar regen issues have been reported due to leaks. The metal gaskets are often smeared with grease which hardens but on refitting this needs to be cleaned as it's too hard a substance to aid resealing if slightly mislocated from original spot. If the smell you detect is coming from the engine bay then there is a leak.

The dpf pressure readings come from dpf pressure sensor (via a small tube from dpf housing) and can read minus but I've not come across such a low reading before. Hopefully it will be a leak causing the low reading but check to see if pipe and hoses to dpf pressure sensor are not blocked

Thanks so much, i will have a look this weekend.

[Crasher]

I can’t remember which way around it is but the calculated and measured loading can be about 5 for one and minus 20 for the other. Take the filler cap off with the engine running to see if you get a whoosh.