The Unofficial BMW M5 Messageboard (m5board.com) - View Single Post - Vanos problem...an obvious problem which dealer says aint there..help needed

DavidS · 24th July 2002, 18:14

Adam,

It might be that you don´t have the usual Vanos noise at startup problem (which is solved by the oil valve), but something different.

Did this problem occur recently? Abrubtly or gradually?

How did you demonstrate the problem to the service people?
Were you there yourself? Was the noise the same as usual?

Whenever you have a problem which only manifests itself when the car is cold, drive the car to the dealer´s parking lot the day before you have an appointment, leave the car overnight to cool.

There is a huge thermal mass in these engines, so it takes a long time to really cool it. Switch the engine off, but leave the key on and set the heating to max, fan to max, open all air outlets, and let it blow until the air feels cold. Then switch on the "use residual heater" button. (which takes heat from the liquid salt thermal reservoir in the cooling system and transfers it to the passenger compartment) and let it blow until the air is cold again. Let the car stand overnight. Then get both the service advisor and the technician to come listen when you start the engine and point out the problem.

It is important to cool the residual heater, otherwise it will warm up the engine quite fast on startup the day after.

David

24th July 2002, 18:14	#7 (permalink)
DavidS Moderator Join Date: Dec 2001 Location: Lund, Sweden Age: 39 Posts: 2,921 Thanks: 0 Thanked 13 Times in 6 Posts	Adam, It might be that you don´t have the usual Vanos noise at startup problem (which is solved by the oil valve), but something different. Did this problem occur recently? Abrubtly or gradually? How did you demonstrate the problem to the service people? Were you there yourself? Was the noise the same as usual? Whenever you have a problem which only manifests itself when the car is cold, drive the car to the dealer´s parking lot the day before you have an appointment, leave the car overnight to cool. There is a huge thermal mass in these engines, so it takes a long time to really cool it. Switch the engine off, but leave the key on and set the heating to max, fan to max, open all air outlets, and let it blow until the air feels cold. Then switch on the "use residual heater" button. (which takes heat from the liquid salt thermal reservoir in the cooling system and transfers it to the passenger compartment) and let it blow until the air is cold again. Let the car stand overnight. Then get both the service advisor and the technician to come listen when you start the engine and point out the problem. It is important to cool the residual heater, otherwise it will warm up the engine quite fast on startup the day after. David __________________ 2000 M5 LeMans blue/Silverstone sport interior, double glass windows, all options except alcantara ceiling and trailer. Michelin PS2 tyres. How to test the MAFs yourself: http://www.m5board.com/vbulletin/e39-m5-e52-z8-discussion/54788-how-test-mafs-yourself-how-mafs-work.html Some further useful threads and info: http://www.m5board.com/vbulletin/e39-m5-e52-z8-discussion/88323-davids-som-useful-threads-info.html Last edited by DavidS; 24th July 2002 at 18:15.