1994 525i BMW, it cranks but it won't start

Check the basics first. Is battery fully charged? This is the most common reason for a no crank, no start. What exactly does it do when you turn the key? Nothing at all, no lights, no 'click' as you turn the key. A slow lazy crank?

lost all our keys,? what is the key story, there sure is one.
no year car told, wow.
E32 model 1986?or (no)
Sixth generation (G11/G12; 2015)???? IMMO does not allow, you to lose all keys, then buy one and start the car, in fact that it is A#1 PURPOSE. to prevent that.

1st google hit, read

https://www.bmwcodingdatabase.com/interesting-about-bmw/readers-ask-lost-bmw-keys-what-to-do.html

Remove battery terminals and clean both posts and terminals
with sandpaper until you see shiny metal. The black coating is lead sulphate which has a high resistance to current flow both into and out of the battery. Also check the battery in you key as the immobiliser may not be reading it.

It could be the key if the vehicle has EWS3, try your spare key.If the battery is full and you torn the key.do you get power on the thin wire to the starter?

BMW 325 325i 1999 2005 Repair Service Manual PDF Click on this link to get solution to your problem instantly

Simple this happens many time either cransensor failed or came loose and is hitting the harmonic balancer. If this sensor fails you will crank and not start, another is cycle the key do you hear the fuel pump come on (it in the trunk area)

Hi.

If it does turn over and electrical works, then the problem is unlikely the battery. You can try jump starting. If it cranks when jump-starting it may be a weak battery, starter motor or alternator, but I don't think that this is the problem.

Check if there is spark on all cylinders. Do a code scanning (this car is OBD1, you will need to do the scan at the dealer place or to find a BMW OBD1 tool- Universal OBD2 scanner will not work on a 1994 BMW). If the codes return misfire or mixture related errors check fuel pressure, check sensors and parts that determine the mixture (MAF/MAP, AIT, O2 sensors, IAC and EGR system), check the vacuum system for leaks and check the crank sensor.

Regards.

Ginko

Need more info. Do you hear the fuel pump kick on when you turn the key to the on position? Does the engine crank over at all?Do your lights go dim when you engage the starter?

shorting to start motor will allow the motor to turn but the ignition system is still off.
try with key turned to ignition position.
suspect starter solenoid on starter motor.
suspect fuses maybe there is a fuse which has blown.
suspect ignition key switch maybe defective.