Replace Bank 1 Sensor 1 (Lambda) O2 Sensor — Top Access (VW Tiguan 2.0 TSI CZPA)

Fault P0135 (O2 heater circuit, Bank 1 Sensor 1) on a 2018 Tiguan 2.0 TSI (CZPA) means the upstream/pre-cat lambda heater has failed. On this engine, the sensor sits high on the exhaust manifold/turbo and is reached entirely from the top of the engine bay — no jacking needed. This guide covers airbox/intake clearance, connector release, removing a carbon-seized sensor with a slotted 22 mm socket, and correct torque. VIN: WVGZZZ5NZJW****** Car: Volkswagen Tiguan Year: 2018 Body type: SUV Engine: CZPA Mileage: 119060 KM Trouble codes: P013500 - O2 Sensor Heater Circ.,Bank1-Sensor1 Malfunction Intermittent Date: 2025-11-20 08:51:43 Mileage: 118828 km

2018 VOLKSWAGEN TIGUAN

Difficulty

Intermediate

Est. time

30- 35 min

Tools

Extra-Long Oxygen Sensor Socket 22mm 1/2"Sq Drive

Parts listed

Fuel

Petrol

Engine

1984cc

Year

2018

Platform

VOLKSWAGEN TIGUAN

Procedure

Step 1: Cold engine + clear top access

Work on a cold engine. Open the bonnet and pull off the plastic engine cover — that's all the access you need to reach the sensor from the top.

Step 2: Locate Bank 1 Sensor 1

The upstream sensor screws into the exhaust manifold, before the cat. On this car it's exposed and easy to see once the cover is off.

Step 3: Disconnect the connector

Trace the sensor lead to its plug, press the tab and unclip it. Keep the harness clear of hot surfaces.

Step 4: Remove the old sensor

Fit the slotted 22 mm O2 socket over the sensor (the slot lets the cable pass) and turn counter-clockwise. It came off without penetrant here; on higher-mileage or rustier cars, spray penetrant and wait ~5 min first.

Step 5: Fit the new Bosch sensor

Anti-seize on threads only (never the tip). Hand-start, then torque to ~45–50 Nm. Reconnect the plug; refit the plastic engine cover.

Step 6: Clear codes & verify

Clear P0135 and drive until readiness completes. Confirm the heater code stays away and fuel trims are within ±10%.

Parts & materials

22 mm sloratchet + extension×1
Bosch Lambda Sensor (Before Catalytic Converter)(0 258 027 215 (LS 27215))×1
Gloves×1
Penetrant spray×1

Planning to do this job?

Save this guide directly to your car's digital logbook. We'll add the required parts to My Inventory and create a Workshop Job with every step ready to tick off.

🚗 Save Guide to My Garage