There is NO need to touch the 4 set screws on the solenoid cover (if you have the style with set screws). These are preset at the factory and should never need to be adjusted or removed!
Sometimes the solenoids will practically fall out of their sockets and sometimes they will not budge. We don't recommend using pliers to remove the solenoids in most cases. There is a lip on each solenoid just under the rubber grommet that it sits in. You should be able to use a small flat blade screwdriver and gently pry each solenoid up, starting with the 2 lower solenoids, then the 2 upper solenoids. If they do not easily move, gently rotate the solenoid back and forth with a pair of pliers or channel locks to loosen them up being VERY CAREFUL not to break the wiring or damage the circuit board,then try prying them again with the screw driver. If they still refuse to budge you can try gently pulling/rocking them with pliers until they start to move. If this still does not work, install the solenoid cover and all 5 bolts but leave them slightly loose, leaving a ~2mm gap between the solenoid cover and the vanos unit. Start the engine for 3-4 seconds and this should force the solenoids loose using oil pressure inside the vanos. You may get some oil leakage so be prepared!
To access the cam sensors, remove the cabin filter assembly and connected air intake elbow from the firewall. You will need a 5mm allen key to remove the bolt holding the CPS in place. It is a very tight fit and a small ratcheting tool will make things much easier here.
The common M5 'diesel rattle' can be attributed to the splined gears that fit at the back of the vanos, connecting the vanos to the cam gears. Each splined gear has a bearing assembly inside which allows it to spin freely with the camshaft. These bearing assemblies are designed with a very loose tolerance from the manufacturer, causing them to rattle or resonate at certain RPM's. At DrVanos we slightly modify these bearings to bring the tolerances much closer together for a tighter fit. By reducing the tolerances in the bearing assembly, the gears no longer resonate and the diesel rattling is reduced considerably. This is a permanent modification that will last the life of the car.
The removal and installation of the splined gears is a fairly complex procedure and not practical for the average DIY owner, but a qualified BMW technician should be able to replace the gears in a few hours. If you are interested in more information about reducing the rattle on your M5 please contact us for more information. We can supply rebuilt gears on a core exchange basis at a very reasonable price.
Solenoid Testing and Repair
Having solenoid issues? Send us your solenoid board and we can test and replace individual solenoids with a quality replacement saving you the cost of a full replacement pack. Call or email for more information. When sending your solenoids in for repair, please include your contact information in the box.
$400.00 per individual solenoid
Splined gear repair service available! DrVanos offers a replacement spindle service to get you back on the road for a fraction of the cost of a new gear set. Just send your broken gears to us and we can replace the spindle for $75 each. Please note that we do not sell the splined M5 gears outright, but you can buy the spindle for $50.