BMW Electrical Sensors, Switches, & Relays for BMW 3 Series E46 (1999-2005)

All vehicles will lose some degree of performance due to heat soak under the right operating conditions.  Engine management systems constantly monitor operating conditions and modifying parameters based on sensor inputs. BMW integrated the intake air temp sensor in the MAF housing on models such as the E39 M5, and, being sandwiched behind a hot radiator and in some applications next to an even hotter valve cover, this is less than ideal for performance applications. Absorbing excess heat from its surroundings, the MAF can’t shed it fast enough, and the ECU reads an inaccurately high intake air temperature. Compensating for this false hot air measurement, the ECU pulls timing and runs a richer fuel mixture, resulting in a significant loss of torque.

What can you do?  Locate an intake air temp sensor in a location where it can properly measure incoming air temps and where it's less prone to heat soak. Mounting the sensor further away from the heat source and isolating it from the MAF housing, it can both resist the effects of heat soak longer and respond to temperature changes more quickly.  The result is you’ll experience reduced torque loss and more consistent power output when you’re pushing your engine hard. 

The Turner engineering team was initially skeptical of the claimed performance benefits of this modification. They first set out validate the functionality and performance benefit of a temp sensor relocation. Replicating stop-and-go traffic heat soak in a 2001 540i was a simple task in a controlled environment - their dynometer. First the car was heat soaked to simulate being stuck in traffic or moving at low speeds by running the car four times on the dyno with the dyno's cooling fans disabled. The fans were then turned on for three more runs to observe the recovery rate once air flow was reintroduced. The test: following this procedure once with a stock IAT, and once with their relocation kit in place. 

The result? Turner recovered 11lb-ft torque at 2500rpm through use of their relocation kit, with even greater recovery to be found for M5 owners. Here are the heat soak-related torque losses Turner experienced:

Stock IAT location:
18rwtq at 2500rpm
10rwtq at 3000rpm
9rwtq at 3700rpm

Turner IAT Relocation:
7rwtq at 2500rpm
5rwtq at 3000rpm
5rwtq at 3700rpm

**Click here for installation instructions**

The Turner engineering team designed a complete plug and play kit (unlike all other options on the market) that makes for quick, easy, and reversible installation. Weather-sealed connectors keep out the elements, while sheathed wiring offers a clean appearance underhood. With a harness nearly 3 feet long - the Turner IAT relocation kit offers flexibility in positioning, but not too long that you're left with unsightly excess wiring. Turner recommends positioning the sensor in a location away from engine heat, but still within the intake ducting to achieve accurate intake temp readings - such as the far side of the base of the airbox. Vehicles with cold air intakes with cone-style filters can even position the sensor in the end of the filter. Simply drill a hole in your (cool) location of choice and plug in the harness. More information including installation instructions and some good examples of sensor mounting locations can be found in our DIY PDF. 

We include everything you need to relocate your IAT, just select your desired sensor brand below - Genuine BMW or original equipment Beru.

Also the perfect plug-n-play option for anyone looking to upgrade their intake to utilize an Alpha-N tune!

Note for vehicles with M62 engine: applicable to 1999 and up

Faulty crankshaft position sensors can cause issues with proper ignition timing and adjustment leading to rough idle, stalling, and potential engine damage. A high quality OEM Hella replacement will have your BMW running smoothly for much less than the cost of a Genuine BMW sensor.

Hella is a premium manufacturer that supplies automotive parts to numerous car brands across the world. Everything from electrical to mechanical genuine parts have been made and supplied directly to BMW before the vehicles ever leave the production floor. Their high quality, long lasting parts have made them a trusted brand chosen to help keep your BMW on the road for many years to come.

As a leading source of high performance BMW parts and accessories since 1993, we at Turner Motorsport are honored to be the go-to supplier for tens of thousands of enthusiasts the world over. With over two decades of parts, service, and racing experience under our belt, we provide only quality performance and replacement parts.  All of our performance parts are those we would (and do!) install and run on our own cars, as well as replacement parts that are Genuine BMW or from OEM manufacturers. We only offer parts we know you can trust to perform!

Fits BMW models with the following engines: M52 S52 M54 M56

The temperature sensor is mounted in either the intake manifold or the intake air box assembly depending on the model of car. This OEM Hella replacement will insure proper readings and fuel/air mixtures for the given temperature.

Hella is a premium manufacturer that supplies automotive parts to numerous car brands across the world. Everything from electrical to mechanical genuine parts have been made and supplied directly to BMW before the vehicles ever leave the production floor. Their high quality, long lasting parts have made them a trusted brand chosen to help keep your BMW on the road for many years to come.

As a leading source of high performance BMW parts and accessories since 1993, we at Turner Motorsport are honored to be the go-to supplier for tens of thousands of enthusiasts the world over. With over two decades of parts, service, and racing experience under our belt, we provide only quality performance and replacement parts.  All of our performance parts are those we would (and do!) install and run on our own cars, as well as replacement parts that are Genuine BMW or from OEM manufacturers. We only offer parts we know you can trust to perform!

This item fits the following BMWs:
1996-1998 E36 BMW 318i 318is 318ti 318ic 323is 323ic 328i 328is 328ic M3
1999-2000 E46 BMW 323i 323ci 328i 328ci
2001-2005 E46 BMW 325i 325ci 325xi 330i 330ci 330xi - M54 engine only
1997-2003 E39 BMW 525i 528i 530i 540i
1997-2001 E38 BMW 740i 740il 750il
2004-2006 E83 BMW X3 2.5i X3 3.0i
2000-2006 E53 BMW X5 3.0i
1997-2002 Z3 BMW Z3 1.9 Z3 2.3 Z3 2.5i Z3 2.8 Z3 3.0i
1998-2000 Z3 BMW M Roadster M Coupe

Used to detect the position of the camshaft, this sensor allows the computer to adjust the ignition timing for optimal performanceand to prevent damage from early or late detonation. Hella replacement sensors will ensure long lasting reliability and will keep your engine running like new.

Hella is a premium manufacturer that supplies automotive parts to numerous car brands across the world. Everything from electrical to mechanical genuine parts have been made and supplied directly to BMW before the vehicles ever leave the production floor. Their high quality, long lasting parts have made them a trusted brand chosen to help keep your BMW on the road for many years to come.

As a leading source of high performance BMW parts and accessories since 1993, we at Turner Motorsport are honored to be the go-to supplier for tens of thousands of enthusiasts the world over. With over two decades of parts, service, and racing experience under our belt, we provide only quality performance and replacement parts.  All of our performance parts are those we would (and do!) install and run on our own cars, as well as replacement parts that are Genuine BMW or from OEM manufacturers. We only offer parts we know you can trust to perform!

URO Camshaft Position Sensor - For BMW M52 M54 Engines

URO Camshaft Position Sensor - For BMW M52 M54 Engines is the perfect solution for restoring proper engine operation when your original camshaft position sensor has failed. This direct-fit OE replacement sensor eliminates trouble codes and check engine lights, ensuring smooth engine performance. Made from high-quality polymer and metal materials, this sensor is designed to withstand the intense heat of your BMW’s engine. With alloy conductors that minimize electrical resistance, the sensor provides accurate operation across all engine RPMs. Built for reliability and long-lasting performance, it’s the ideal choice for your BMW M52 or M54 engine.

Key Benefits:

• Direct-fit OE replacement for easy, plug-and-play installation
• Restores proper engine operation by eliminating trouble codes and check engine lights
• High-quality polymer and metal construction withstands the intense heat of the engine
• Alloy conductors minimize electrical resistance for precise operation at any engine RPM
• Engineered for reliability and longevity, providing long-term performance and peace of mind

Upgrade your BMW M52 or M54 engine with the URO Camshaft Position Sensor and enjoy reliable engine performance.