VANOS solenoid or timing chain?

My 540i engine was running very rough and making metal rattling sounds. My diagnostic tool said VANOS solenoid cyl 1-4. I changed it out with new one and engine ran great but sounds continued. I drove it a few miles hoping it would clear up, but engine suddenly died and won't restart. Diagnostics now say both VANOS solenoids bad and both camshaft position sensors bad. Looking through oil filler cap opening on #1-4 side, the timing chains appear to be intact, but I haven't opened up the covers to see if the #5-8 are OK. Before I start any major surgery, has anybody out there had the same experience? Help!

Sorry to be the bearer of bad news but its the timing chain guides. Now that you have driven it and it won't start it sounds like it may have jumped timing. Hopefully you haven't bent any valves.

Do your search for the TCG replacement and the parts needed, plenty of threads on forum. Your gonna need the timing tools/cam lock down locks to do it right. It's gonna run you about $800 plus to do it correctly. It's not hard, just time consuming as you have to remove the complete front of engine.

Good luck and report back on progress.

Would be useful to other if could post your mileage?

I agree that they timing chain guide rail have worn out. Hopefully there is no internal damage from you driving it. I think it a 20+ hour job in the book so your looking at a big repair bill at a shop to get it done. If you handy with the tool you can do it yourself, a long job but not too hard. A good opertunity to do a few other things while your there, vanos seals, water pump etc.