Triggers:Bosch Quick Start

VW/Audi 1.8T Bosch Quick Start

VW/Audi VR6 Bosch Quick Start wheel

The Bosch Quick Start camshaft trigger pattern was introduced in the early 2000s by Bosch on the Motronic ME7.x engine management systems and it carried into the late 2010s on some engines.

From the VW Self-Study Programme 195:

The quick start wheel is secured to the camshaft. The signal it sends enables the engine control unit to recognise more quickly the position of the camshaft in relation to the crankshaft and, in conjunction with the signal which the engine speed sender generates, to start the engine more quickly.

Volvo B5204T4 Bosch Quick Start wheel

In previous systems the first combustion cycle was initiated after a crank angle of approx. 600-900°. The quick-start sender wheel enables the engine control unit to recognise the position of the crank-shaft in relation to the camshaft after a crank angle of only 400-480°.

As a result, the first combustion cycle can be initiated sooner and the engine starts more quickly.

Some engines have a dual hall-sensor with two outputs and it can seem that the signal is implausible. Switch the output to the other sensor and try again (VR6 for example).

Engines that use Bosch Quick Start are (but not limited to):

• VW/Audi 1.8T (ME7.5 only, ME3.8.3 uses Single Tooth)
• VW/Audi 2.3 VR5
• VW/Audi 2.8/3.2 VR6
• Volvo 850 (B5204)
• Alfa Romeo Twin Spark 1995 - 2005
• Various BMWs
• Many others