My BMW 318i doesnt engage in any gear, it just iddles.

BMWs in the 3 Series and 5 Series that come with the 5-speed ZF transmission commonly experience problems with torque converter delamination. Drivers will notice signs of this problem when the car appears to shudder or misfire at around 40-50km/h.
This BMW transmission problem needs to be repaired as soon as the first signs are noticed. If you drive until the converter lining actually fails, it can destroy the entire pump assembly in the transmission. This will require a complete reconditioning of the automatic transmission.
BMW drivers are cautioned that it is better to spend a little now, rather than a lot later.
Apart from the problem with the torque converter delaminating, these 5-speed transmissions commonly suffer breakage of the D/G cylinder. If this breaks, the car loses reverse gear. This automatic transmission problem is another that requires a total transmission overhaul to repair.

Hi there.
Well because its a auto box you could have a band or pump problem which is in the gear box and is bathed in auto matic fluid oil and that could be your problem as the bands do wear down fast on a lot of cars and BMW with there power that could be you.
So take it to a auto box people and get it checked out.

Check engine light? If not try changing the transmission filter.

have the transmission serviced
dirty oil causes what is indicated
run the fault codes to find other sensor problems

Failed Transmission

Time for a Rebuild

need to find where the oil is going. I take it for granted you sre using the correct transmission fluid Dexron 11

Hey
How du i mount my tacho rings in my instrumentpanel.
my car is an BMW 318i E46 from 2002

Check the transmission release bearing and the gearing of the transmission check if you need to replace the release bearing.

I’m happy to assist further over the phone at https://www.6ya.com/expert/ramy_d9e7ebea3891f482

remove the gear shift panel and with super gleu secure the gear indicatop in the correect position

check the cluster fuse?