Show picture of bmw 320d e90 2007 timing chain tensioner

https://www.newtis.info/tisv2/a/en/e46-320d-lim/repair-manuals/11-engine/11-28-drive-belt-with-tensioning-deflecting-element/BzRYhMS at the bottom of the page

• Camshaft alignment/locking tool - BMW No.11 6 320.
• Flywheel locking tool - BMW No.11 8 010 (AT version GM-5).
• Flywheel locking tool - BMW No.11 8 182/11 8 183 (AT version 6HP-19).
• Flywheel locking tool - BMW No.11 8 182/11 8 183/11 8 185 (MT version H).
• Flywheel timing pin - BMW No.11 2 300.
• Timing chain tensioner locking pins - BMW No.11 3 340.

• Here are some general precautions
• Disconnect battery earth lead.
• Remove glow plugs to ease turning engine.
• Turn engine in normal direction of rotation (unless otherwise stated).
• Observe tightening torques.
• Do NOT turn crankshaft via camshaft or other sprockets.
• Do NOT turn crankshaft or camshaft with timing chain removed.

for more info email me at [email protected]

AT A GUESS ONE OR MORE OF THE PULLEY WHEELS IS THE TENSIONER

the error codes are BMW specific and yes an error code would show up as a cam position sensor fault.

it has a belt.

its got a timeing chain so dont try to change it

if you go to the dealer they will copy the mech manule it you ask them as they want you to get frustrated and take it to them
so go on and ask and if all else fails take it to them or goto local parts store like auto zone they can preint it off too
dealer is best bet though