CRANK POSITION SENSOR?????

[corradokenny 0]

Hi guys, as above can someone explain wot it does and how to fix it????????

My 94 vr6 sometimes turns over a bit to long before it starts, cleaned the ISV but still does it?????

[ziderapple 0]

A crank position sensor is a component used in an internal combustion engine to monitor the position or rotational speed of the crankshaft. This information is used by engine management systems to control ignition system timing and other engine parameters. Before electronic crank sensors were available, the distributor would have to be manually adjusted to a timing mark on the engine.

 

The crank sensor can be used in combination with a similar camshaft position sensor to monitor the relationship between the pistons and valves in the engine, which is particularly important in engines with variable valve timing. It is also commonly the primary source for the measurement of engine speed in revolutions per minute.

 

Crank sensors in engines usually consist of magnets and an inductive coil, or they may be based on magnetically triggered Hall effect semiconductor devices. Common mounting locations include the main crank pulley, the flywheel, and occasionally on the crankshaft itself.

[Yandards 0]

Right, if your crank position sensor (G28) is bust on a VR the engine wont start, so if it does start it is not the crank position sensor.

 

If you use VAG-COM on a non-running engine it will throw up a G28 error but as soon as it starts then it will clear, just to prove this unplug the crank position sensor (front of the block near the gearbox end white plug) and crank the engine it wont start.

 

The other sensor with a similar name is the cam position sensor (G60) or on early VR's with a dizzy this is the hall sensor in the dizzy. The car will start with this disconnected or broken but the engine doesn't know if it is in the No.1 or No.6 TDC so it will operate fully retarted by 12 degrees, resulting in around 20bhp/lbft torque power loss.

 

VRs don't generally start at the first turn of the key, so I would not be too concerned.

[dr_mat 0]

Signs of a failing crank sensor are:

- engine hiccups when warm,

- followed by complete failure when hot

- followed by a refusal to restart until it cools down.

 

Anything but this is probably caused by something else ...

[Kevin Bacon 5]

The other sensor with a similar name is the cam position sensor (G60) or on early VR's with a dizzy this is the hall sensor in the dizzy. The car will start with this disconnected or broken but the engine doesn't know if it is in the No.1 or No.6 TDC so it will operate fully retarted by 12 degrees, resulting in around 20bhp/lbft torque power loss.

 

Without a cam sensor the ECU can't fire the injectors sequentially either, so switches to grouped injection, which will be a very rough and ready fuel map, and with no ignition advance.

 

VRs don't generally start at the first turn of the key, so I would not be too concerned.

 

If you lose the Bosch injectors and dial in some more cranking fuel, it'll start on the button.