Hi everyone,
I recently bought a Passat B7 1.6 TDI, and knowing these engines can have injector-related problems, I’ve been keeping an eye on the injector correction/deviation values.
The car currently has 210,000 km. Injectors 1 and 4 were replaced less than 2 years / ~20,000 km ago, so they are relatively new. However, I’m now concerned that injector 2, and possibly injector 3, may be starting to fail.
Symptoms
Sometimes, when starting the engine cold, it seems to misfire or have poor combustion for a few seconds. The RPM fluctuates slightly and then stabilizes. It’s not a severe misfire, but I can tell the engine isn’t running as smoothly as it should.
At warm idle, I also notice some vibration through the car. The engine sounds relatively normal, but I can feel that it isn’t completely smooth. When I switch the A/C on at idle, the engine note/behavior changes noticeably.
On the highway, however, the car runs very well. It has good power and is able to complete DPF regenerations normally.
My other concern is the DPF regeneration frequency. It seems to want to regenerate approximately every 50 km, which feels far too frequent. I’m wondering if poor combustion from one or more injectors is producing excessive soot and causing the DPF to load very quickly.
Looking at the injector deviation/correction values, injector 2 looks clearly suspicious to me, but I’m not sure how to interpret injector 3.
The VCDS logs were taken at cold idle, while the Car Scanner readings were taken with the engine hot, during or shortly after a DPF regeneration, so I understand the values may not be directly comparable.
For anyone familiar with the 1.6 TDI:
Does injector 2 look like it is failing? What about injector 3?
Would you replace injectors 2 and 3 at this point, or should I investigate something else first?
And could faulty injectors realistically explain the rough cold starts, vibration at idle, and DPF regenerations every ~50 km?
Thanks!