Car stalls while you drive sometimes. It stalls

Check crankshaft sensor.

try your crank sensor

Have the throttle body looked at!

I have a 1989 5-series BMW which sometimes stalls after changing from reverse to drive. It also sometimes shakes when first driving in reverse before changing to drive.

Fuel filter?

check the key my sure the programme is still good

Check the EGR valve. Sounds like the three stage EGR valve is acting up. Look for any discoloration around the valve ports. This valve is located on the intake manifold near the throttle body.

Here is the most common cause of surges and stalls and low idle, it is the idle speed control air-bypass valve and throttle valve (IAC for short), they get full of gunk over the miles and cause idle issues (stalls, low idle) like yours, Get a can of intake cleaner from any local parts store, not carb spray, intake cleaner, it is made by a company called CRC, remove the air intake hose to the engine, hold the idle high so the engine won't stall, then spray the can of cleaner into the intake while keeping the engine running, use at least 1/2 the can, shut down the engine and disconnect the battery for 5 minutes, then restart and complete a number of mixed driving cycles, town, freeway, stop and go etc., after a few days the problem will go away as the system will relearn to the clean intake.

You have one of two very common problems.
Number one may be a stuck open EGR valve
Number two would be a failing Idle Air Control valve (IAC).
Try this: Open the hood & locate the EGR valve, close to the firewall, behind the intake. Find & take with you a small hammer. The next time that it happens, open the hood & tap on the EGR valve. If it is sticking "open" the tapping may dislodge the carbon particles that are keeping it open.When the EGR valve is open, exhaust is getting into the intake at idle, and this will def stall out the car.
There is no repair to the IAC valve, it would need to be replaced if it is bad.
One of these two scenarios will cure your problem, I see it every day.

ive seen fault crank positon sensor cause this also clogged injectors cause this ,for sake of saving money try some chevron techron injecttor cleaner but if u end up having take this car in i would go to the dealer cause all places charge the same 4 labor n lot small shops cause more damage than they fix