On my 1998 US Model 318ti, the battery is located under the hood, on the right side, against the firewall, in a plastic battery box. See the related link for a photo of the engine bay, with the battery box top removed.
behind the battery
A BMW 318ti should have a 12V 55Ah CCA (SAE) 450A fitted if it's an E36 model
Chain
no dipstick.
The front oxygen sensor is located on the exhaust manifold of the BMW 318ti. The rear oxygen sensor is located in the head pipe.
For the 1998 BMW 318ti, the radio battery constant 12-volt + wire colors are red and white. The 12-volt radio accessory wire colors are purple and white. The ground wire is brown and the antenna trigger wire is white.
169 miles per hour
Don't know about the E46, but my 97/98 318ti locks and unlocks with the central locking.
routing diagram BMW 3 series serpentine belt
Yes. The 318ti was a two door hatchback.
The BMW 318 has only one belt. All of the components of the engine are driven by a single serpentine belt.
3 or 300