YanCT
Active member
Hi Everyone,
I drive a 2014 MK7 Golf (with R body) with CLHA engine (1.6 TDI 105hp) modded to 215hp and 420nm on roller test bench. I really like this car and the drivability is amazing, all the mods are well supported and the car gives power and torque from low RPM to high RPM. The car is fuel efficient (4.5L/100kms to 6.5L/100kms).
But from my last mod (207hp-->215hp with almost no smoke, finally ! ) I'm experiencing injectors knocking and I will need your help to find the bad injector(s) to replace.
First, that's the mods :
- Original turbo (GTD1244vz) has been replaced with the MK7 GTD's Turbo (GTD1449vz)(max press. 1.8bars)
- DPF and Catalyst and EGR has been removed (complete downpipe, original rear muffler still here)
- Oil Catch Can
- BMC Carbon Intake
- Original Injectors (04L 130 277 G - Bosch system) has been replaced with the MK7 GTD's Injectors (04L 130 277 AE - Bosch system) (the purpose in this was not to get more power but to reduce diesel smoke thanks to bigger nozzle and pressure increase, we can shorten injection duration and so reduce smoke).
The last mod is the why I'm coming on this forum.
During Injectors replacement, all seals has been replaced and correctly inserted. All things has been cleaned before inserting injectors.
Injectors has been adapted with their respective IMA-ISA codes using VCDS and all went well.
After replacing injectors with the GTD's ones, the ECU has been remapped by my Tuner (the same who follows and tunes my car since always.
The problem is :
- When engine cold, I hear a really loud knocking and I can feel a lack of power on low RPM. Everything is fine after 1800-2000rpms. Noise appears on middle and full throttle. Never on idle.
- When engine warm (coolant 90 to 100 °C and oil 95 to 110 °c) it disappears but still appears sometimes for few minutes. Always on low RPM and only when full throttle. Never on idle.
- Engine cold start makes a knocking injection noise on the first RPM then it idles normally.
- Cold start AND warm start sends a tiny white-grey smoke at exhaust pipe (see video down this message)
- Sometimes, I can hear the knocking noise when the car is downhill with no injection (for example engine brake on 3rd gear) but the noise is way quieter and you really need to listen carefully. It's not systematic.
On EDC17 and Bosch injection system there is no Basic setting of injectors (only the IMA-ISA codes but that's OK) so I decided to investigate and I have some doubts on injector 2.
1/ I ran a VCDS log session of injectors deviations on idle on cold start and warm start. Nothing looks suspicious to me.
Cold start :
Warm engine :
2/ I then ran physical test of injectors deviation. On idle and warm engine only. (maybe do you have suggestions ?).
All bottles got filled to exact same level (Test duration : 5 mins)
3/ I decided to take the VCDS on road and perform a test under load :
I drove to a big hill, started 1st gear then 2nd gear and finally engaged 3rd gear on a really low RPM ( 1100 rpms) and full throttle. That was the only way I found to force my engine to send maximum fuel possible. The car really slowly took RPMs and I've been able to see injector 2 with big and positive numbers.
4/ Took originals injectors back to double check... and all noises went back to normal (after IMA-ISA adaptation). But the car is laggy as this injection map is not adapted for such little nozzles.
I then put back the big injectors (and IMA-ISA), and the noises are back...
What are your thoughts please ? I have ordered a new injector and it's on his way, but I don't know which one should I remove to put the new one in.
Why is it impossible to get a concluant test on idle ? What is this strange noise I can hear on downhill on engine brake with no injection ? (it disappears with the original injectors)
I don't understand the - and + values. What does it mean ?
Can I rely on my step 3 ? As I never saw this method mentioned in any forum...
Thanks a lot for you future replies !
The video of cold startup with the little smoke :
I drive a 2014 MK7 Golf (with R body) with CLHA engine (1.6 TDI 105hp) modded to 215hp and 420nm on roller test bench. I really like this car and the drivability is amazing, all the mods are well supported and the car gives power and torque from low RPM to high RPM. The car is fuel efficient (4.5L/100kms to 6.5L/100kms).
But from my last mod (207hp-->215hp with almost no smoke, finally ! ) I'm experiencing injectors knocking and I will need your help to find the bad injector(s) to replace.
First, that's the mods :
- Original turbo (GTD1244vz) has been replaced with the MK7 GTD's Turbo (GTD1449vz)(max press. 1.8bars)
- DPF and Catalyst and EGR has been removed (complete downpipe, original rear muffler still here)
- Oil Catch Can
- BMC Carbon Intake
- Original Injectors (04L 130 277 G - Bosch system) has been replaced with the MK7 GTD's Injectors (04L 130 277 AE - Bosch system) (the purpose in this was not to get more power but to reduce diesel smoke thanks to bigger nozzle and pressure increase, we can shorten injection duration and so reduce smoke).
The last mod is the why I'm coming on this forum.
During Injectors replacement, all seals has been replaced and correctly inserted. All things has been cleaned before inserting injectors.
Injectors has been adapted with their respective IMA-ISA codes using VCDS and all went well.
After replacing injectors with the GTD's ones, the ECU has been remapped by my Tuner (the same who follows and tunes my car since always.
The problem is :
- When engine cold, I hear a really loud knocking and I can feel a lack of power on low RPM. Everything is fine after 1800-2000rpms. Noise appears on middle and full throttle. Never on idle.
- When engine warm (coolant 90 to 100 °C and oil 95 to 110 °c) it disappears but still appears sometimes for few minutes. Always on low RPM and only when full throttle. Never on idle.
- Engine cold start makes a knocking injection noise on the first RPM then it idles normally.
- Cold start AND warm start sends a tiny white-grey smoke at exhaust pipe (see video down this message)
- Sometimes, I can hear the knocking noise when the car is downhill with no injection (for example engine brake on 3rd gear) but the noise is way quieter and you really need to listen carefully. It's not systematic.
On EDC17 and Bosch injection system there is no Basic setting of injectors (only the IMA-ISA codes but that's OK) so I decided to investigate and I have some doubts on injector 2.
1/ I ran a VCDS log session of injectors deviations on idle on cold start and warm start. Nothing looks suspicious to me.
Cold start :
Warm engine :
2/ I then ran physical test of injectors deviation. On idle and warm engine only. (maybe do you have suggestions ?).
All bottles got filled to exact same level (Test duration : 5 mins)
3/ I decided to take the VCDS on road and perform a test under load :
I drove to a big hill, started 1st gear then 2nd gear and finally engaged 3rd gear on a really low RPM ( 1100 rpms) and full throttle. That was the only way I found to force my engine to send maximum fuel possible. The car really slowly took RPMs and I've been able to see injector 2 with big and positive numbers.
4/ Took originals injectors back to double check... and all noises went back to normal (after IMA-ISA adaptation). But the car is laggy as this injection map is not adapted for such little nozzles.
I then put back the big injectors (and IMA-ISA), and the noises are back...
What are your thoughts please ? I have ordered a new injector and it's on his way, but I don't know which one should I remove to put the new one in.
Why is it impossible to get a concluant test on idle ? What is this strange noise I can hear on downhill on engine brake with no injection ? (it disappears with the original injectors)
I don't understand the - and + values. What does it mean ?
Can I rely on my step 3 ? As I never saw this method mentioned in any forum...
Thanks a lot for you future replies !
The video of cold startup with the little smoke :
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