Skoda Yeti 1.2 TSI Smoking

Topic: 2013 Yeti 1.2 TSI (CBZA) – Excessive Grey/White Smoke After Turbo Replacement

Vehicle Specs:

• Model: 2013 Skoda Yeti 1.2 TSI (EA111 Engine - Chain Driven)

• Mileage: 54,000 miles

• Initial Fault: Heavy white/grey smoke. Diagnosed by previous garage as a failed turbo (quoted £2k).

Current Symptoms:

• The Smoke: Thick white/grey smoke, most prevalent on cold starts. It tends to calm down after a drive but returns aggressively after a short soak and restart.

• Tailpipe: Heavily sooty/carbon-coated, but not oily.

• Fluids: Coolant level is stable (no signs of HG failure). Oil consumption is noted, but the smoke lacks the typical blue tint of burning oil.

• Spark Plugs: Cylinder 3 plug was found black/oily; the others were normal.

Work Completed to Date:

• New Turbocharger installed.

• Oil and Filter service.

• New Spark Plugs, Leads, and Coil Pack.

• Catalytic Converter removed/inspected (found to be clean/not blocked).

The Diagnostic Dilemma

The car presents as if it is severely over-fuelling. Despite the "white" appearance, the soot levels and lack of coolant loss suggest unburnt fuel rather than steam.

Current Theories:

1. Leaking Injector: Specifically on Cylinder 3, given the state of the old plug. It may be "weeping" while the engine is off, leading to a fuel-heavy start.

2. Oxygen (Lambda) Sensors: New sensors are on order, as skewed readings might be forcing a rich trim.

3. Valve Stem Oil Seals: Considering this due to the oil consumption, though it doesn't quite explain the "over-fuelling" soot.

4. High-Pressure Fuel Pump (HPFP): Possible internal seal failure leaking petrol into the oil, though the oil level isn't rising.

The Question: Has anyone encountered this specific behavior on the 1.2 TSI? Before I commit to stripping the head for stem seals or replacing the injectors, are there any known sensor or software glitches that cause this specific "sooty-white" smoke profile?