Bosch 16749 Oxygen Sensor - Downstream, Downstream Right or Upstream

Bosch Actual OE Oxygen Sensor 16749

Bosch 16749 is an Actual OE oxygen sensor built for precise air-fuel ratio feedback to the ECU. It supports stable combustion control and emissions management for Mercedes-Benz and Smart applications that use a narrow-band heated downstream or upstream sensor.

Key Features

• Actual OE Oxygen Sensor from Bosch
• Narrow-band heated sensor design for fast closed-loop response
• Specific fit with threaded mounting and 18 mm thread size
• 4-wire configuration with included wiring harness
• Rectangle female connector with pin terminals
• Metal housing with high-temperature-resistant construction
• 10 in wiring harness length and 13.4 in overall length
• Hex size: 22 mm

OE-Style Sensor Performance

Bosch has developed oxygen sensor technology for decades, starting with early thimble-style designs and later advancing to planar narrowband sensors for quicker light-off and more accurate lambda control. Part number 16749 uses a heated narrow-band design with ceramic sensing elements and optimized heater control to deliver consistent signal quality under thermal and vibration stress. This Bosch Actual OE Oxygen Sensor 16749 is a direct replacement choice for Mercedes-Benz C63 AMG, GL450, GL550, GLK350, SL550, SL63 AMG, and related applications where precise downstream or upstream feedback is required.

This part cross-references Mercedes-Benz OE numbers 0035428218 and 0045420718 for the same application.

What It Helps Address

• Check engine light related to oxygen sensor signal faults
• Incorrect air-fuel ratio feedback to the ECU
• Slow closed-loop operation after startup
• Emissions test failures tied to sensor response issues
• Rough combustion control caused by degraded sensor output

Installation Notes and Tips

Compatible With 2005-2015 Mercedes-Benz and Smart applications listed in the fitment data, including 2008-2015 Mercedes-Benz C63 AMG, downstream; 2008-2015 Smart Fortwo, downstream; 2013 Mercedes-Benz R350, downstream right; 2006-2011 Mercedes-Benz R350, downstream right; 2007-2012 Mercedes-Benz GL450, downstream right; 2008-2012 Mercedes-Benz GL550, downstream right; 2010-2012 Mercedes-Benz GLK350, downstream; 2007-2012 Mercedes-Benz SL550, downstream; 2009-2012 Mercedes-Benz SL63 AMG, downstream; 2006-2011 Mercedes-Benz B200, upstream and downstream; 2010-2011 Mercedes-Benz C250, downstream; 2008-2011 Mercedes-Benz C300, downstream; 2006-2011 Mercedes-Benz C350, downstream; 2007-2011 Mercedes-Benz CLS550, downstream; 2006-2011 Mercedes-Benz E350, downstream; 2007-2011 Mercedes-Benz E550, downstream; 2006-2011 Mercedes-Benz ML350, downstream right; 2008-2011 Mercedes-Benz ML550, downstream right; 2009-2011 Mercedes-Benz SLK300, downstream; 2005-2011 Mercedes-Benz SLK350, downstream; 2006-2009 Mercedes-Benz C230, downstream; 2006-2009 Mercedes-Benz CLK350, downstream; 2007-2009 Mercedes-Benz CLK550, downstream; 2007-2009 Mercedes-Benz CLK63 AMG, downstream; 2006-2008 Mercedes-Benz SLK280, downstream; 2006-2007 Mercedes-Benz C280, downstream; and 2007 Mercedes-Benz S550, downstream right.

Verify connector shape, wire count, mounting thread size, and sensor position before installation. Use the vehicle service information for the exact bank and sensor location, and inspect the harness routing to avoid heat or abrasion damage.

Quality Assurance

Bosch backs this oxygen sensor with OE development experience and materials selected for durability in high-heat, high-vibration exhaust environments. The Bosch Actual OE Oxygen Sensor line is built to deliver OE-proven fit and signal behavior for emissions control service.