Golf Mk6 CFHC Engine Clicking when cold

**Jon44w** · 03-03-2019,09:25 PM

Ive got a 2010 Mk6 CFHC 2.0 Tdi 140 engine with about 120k miles that makes a clicking noise and very slight misfire when driven from cold.

This only happens first thing in the morning and I can avoid it from happening by letting the car warm up for 15/20 mins before driving. The clicking is first noticable about 1200 rpm and is louder when driving up a hill with more load on the engine. After a 15 min drive you would never know the problem was there. The car is perfect. I should add there is no clicking if revved in neutral.

No fault codes on vcds scan. Any previous experience or advice is much appreciated.

**Jon44w** · 13-06-2019,08:38 PM

Problem solved.

It turns out injector 2 was leaking diesel overnight which was causing the misfire in the morning. VCDS showed injector 2 reading stuck at + 3.0 (Im assuming this is the max reading possible) When the car was cold but strangely when the car warmed up and cleared the misfire (max 20 seconds) it ran perfect for the rest of the day and all injector readings normal!

The customer didnt want to pay for a new injector so got a used one off EBay. I didnt code the replacement injector either as I believe if I did then the ECU would think a brand new injector was fitted and not allow for the wear in the second hand one. Im not sure if this is a good idea or not but the engine sounds perfect. Any thoughts or comments are much appreciated.

Hope this helps anyone else with the same issue.

**Crasher** · 13-06-2019,10:02 PM

I would have entered the new code but then again we won’t fit used injectors, used just about anything... I have lost more time and sleep over used parts during the last 40 years than I care to think about. I let my guard down once a few months ago and gave into pleading then spent two days with the car dead on the lift whilst another part was chased down. I used to get cheeky sods who gave me a used part to fit and then when it failed expect me to do the labour FOC!

**Jon44w** · 13-06-2019,10:05 PM

Totally agree with you, I urged him to buy new but it wasnt happening. I would have liked to code in the injector but the way the car ran without coding was too good to risk even trying. In a perfect world we would all have loads of £££ to spend but sadly its not the case.