A owner of BMW E60 523Li made 2007 with N52 2.5L engine described that engine idle vibration occurs intermittently.Technicians had repaired the 523Li twice,and finally solved engine idle vibration.So I write this article to share the expericen of how to solve BMW 5 series engine idle vibration.Hope this article can help you solve what you suffer.
Technician diagnosed the 523Li and found the misfiring of second engine cylinder.
Possible Reasons of engine cylinder misfire:
1.Ignition system:high failure probability,it will take a little time to fix,priority option.
2.Automotive variable valve timing system:Medium failure probability,it will take you long time to fix,as a second choice.
3.Fuel injection system:Low failure probability,check this point on the last look.
4.Intake and exhaust systems:exclude it after detecting.
5.The issues of piston ring and engine valve also can coused this problem,but all of them in low probability,you can check this option in the end.
Considering the situation that the car suffered many time trouble on ignition coil,and BMW Company also has related technical notice.We followe the principles of easy-to-complex,to replace 6 ignition coil and spark plug,and tell owner continue to observe engine idle vibration.
After a month later,the 523Li engine idle vibration occured again.Technician use diagnostic tool to read DTCs,it show that”engine cylinder take turns to misfire from 1-6 cylinder” and the exhaust camshaft deviated 40° compare to the normal position.So we focus on the BMW VANOS.
Technicians disassembled VANOS,and replaced solenoid valve of VANOS,camshaft position sensor,exhaust VANOS actuator,relevant seals.Finally replace the new engine valve chamber cover pad and screws.
After finish this procedure,technician ask to drive 523Li back,and observe vibration situation when driving.8 months later, 523Li ask for second maintenance, idle vibration failure no longer appeared.