Z3 Roadster (E36/7) Having some mechanical problems.

So yesterday i was driving my car. It worked fine in the morning, and on the way to work, but when i got out of work i ran into problems. When i turn the key the car cranks, turns on for two seconds, and then turns back off. Does anybody know what this could be.
(definitely not the battery)

it is getting to sound like an ignition switch or a relay. more testing /checking is needed

Get codes read.

I am not exactly sure, but it is mostly because i am pretty young and i am still getting into the swing of things. Like i stated before, it starts up, idles for a little jitters and then turns off. Me and my father were talking and we were saying how it could possibly be the fuel pump/ fuel filter.

It could almost be anything. Maf. Tps. Crank angle sensor. Vvt sensor. Bad gas. Coils. Plugs. Get codes read as stated above. Or buy your own scanner as you will need run in the future anyway.

Sounds like a good idea. Could you link me to a good one to buy? And is there a manual that tells you what the codes mean?

I bought my ob2 reader from harbor freight. It was 129.00 dollars and does everything the 300 dollar snap on one does. Live data reading ect. It tells you what the codes are so no reason to google crap after you read it. Also clears codes of course. Mine has more than paid for itself I use it constantly.

Centech is the brand

It ended up being a bad relay.