Quote:
Originally Posted by matteblue3er
Quote:
Originally Posted by sa1lor
I honestly do not know. But he did not replace the VVT motor, it's still the original one. But he obviously did have to remove it when he replaced the valve cover. Do you still have to have to relearn the end stops if you don't replace the motor with a new one? Also, what does "relearning the end stops" actually mean?  |
You should relearn end stops anytime the VVT motor is removed. If it's replaced EXACTLY how it came out, you can sometimes get away with not relearning the stops. But if you have the tool, the procedure takes minutes and is a no brainer to do to have peace of mind.
The ESS sensors do not know what the start and stop position is. The calibration procedure lets the sensor (or rather DME) know the absolutely min and max shaft positions.
The procedure at ignition switch is a self-test procedure that verifies shaft position and that there is no obstruction in the system. It makes sure it can fully actuate the eccentric shaft from min to max. (This is cycling sound you hear) This does NOT relearn end stops.
If you don't relearn end stops and the shaft is out of sync, the sensor will read that the shaft has exceeded the min or max positions and throw faults. |
As far as I know, you only need to turn the ignition on and wait a few seconds before starting the engine. This gives the DME time run the Eccentric cam to the stops.
Yes it will store a fault but if given time to relearn it will run fine.
The DME initiates the relearn anytime it measures a movement in the eccentric cam when powered up.
If it's not given time to relearn and you start the engine, you will get the error plus Emergency mode.
At least this is how my E85 worked.
Not much difference to me anyways, I used INPA so much for checking and clearing, I can't imagine working on a BMW without it.