What causes misfiring or malfunction of cylinders in bmw 325i 2002 model engine

SOURCE: check engine light comes on but car runs great 2002 bmw 325i and

The check engine light could be any number of things and the only way to find out is have the codes scanned. The brake light issue is common on E46 3 series. It is an issue were the brown ground wire that goes into the lamp housing melts at the connector causing a loose ground connection. The connector needs to be replaced and also add additional grounding wires to prevent further issues. And for fuel additives either use the cheveron techron, or the bmw fuel additive(the bmw stuff is the exact same thing, so just use which ever is cheaper).

SOURCE: misfire on cylinder 4 & 5. combustion miss with cylinder cutout.

the best way to diagnose a misfire is to move the ignition coils of those cylinders(4 and 5) to different cylinders to see if the misfire will move. you can also move the injectors around and even the spark plugs.(make sure to keep a good record of where you are moving them). if you can't get the misfires to change cylinders. your next step would be to do a compression check on all cylinders. air leaks in the intake system can cause misfires but usually it isn't on the same cylinders all the time

SOURCE: 96 bmw 740il misfire

This is a pretty common problem. I would change your valve cover gaskets. They run around ~ 50 bucks. If they are bad it will leak oil into spark plug well and cause a misfire. Very known on the 740.. Also if tune was not anytime not too long ago id change spark plugs while you at it. Then clear the computer and if you still get misfire on 8 try changing the ignition coil which is right about the cylinder with cylinder ignition coil 5. clear the computer. if you get random misfire and misfire cyclinder 5 after then its your ignition coil. parts store runs around 100 bucks

SOURCE: 2001 bmw 325i is misfiring?

misfire happens because there is still fuel not burned in the cylinder so when its pushed out its burned in exhaust tube because the heat thats why you hear these small explosions. this caused if your sparking pluge not firing well . or there is a leak in the intake valve . in your case i advice you to check your sparking plug . if this helped pls vooote

SOURCE: 2006 BMW 325i E90 remote programming

That remote you purchased, did you remove your vehicle key from your old one and insert it into the new one? At the back of the remote there are pinch grips, pinch and pull to remove the key, you should have a plastic version of this key for your car, in the spare in the glovebox, unless it has been removed, check also in the owners manual folder, if you bought this car used it maybe in there. If you do not have the kaey that matches your car to put in the remote it will not program to the car. Hope this helps, let me know.