Sorry you’re having car trouble! The OBD port location in a BMW E30 is likely underneath the dashboard on the driver’s side, above the hood release handle.
If it’s not there, you can find the OBD port on other BMW
vehicles on the center console next to the cigarette outlet. You may have to remove a small bit of material with a flathead screwdriver to access the OBD2 port. Your BMW E30 was made before 1996, so it has an Onboard Diagnostics I (OBD-I) system, which is a simpler system than the OBD-II system used in modern cars.
Most scan tools will not work for OBD-1 cars. Our recommendation would be to take your E30 to a certified mechanic or to a BMW dealership to diagnose the issue.
If you’re bent and determined to do the test yourself, you might try performing a Stomp Test on your BMW E30.
Get in your vehicle and shut all of the doors.
Turn the key in the ignition to the On position.
Fully depress the accelerator pedal, then completely release it. Repeat this five times within 10 seconds.
A code should flash on your dashboard as a succession of blinks with a pause between each number.
If there are no faults, the code will flash “1444”.