I own a 2001 M5 (build 10/00) with a problem I have not encountered or heard about. Yesterday, while driving normally around town (non spirited...) the exhaust note of the car dropped about 2 octaves and got significantly louder, just as if there had been a hole in the exhaust manifold or system. At the same time, the SES light popped on.
I was close to a mecahnic/friend with a lift in his garage and drove over, only to have the sound change to normal in ten minutes or so. SES light remained on. Got the car in the air; absolutely no problem anywhere with the exhaust system. Drove it home, normal sounding exhaust note, SES light still on and called service advisor last night.
This morning I start the car to move it to take another vehicle to the office, no SES light, no change in exhaust note, still normal. Waiting for a call from the dealer.
The car has around 12,000 miles on it, only modification is a Dinan exhaust which has been on the car for a long while, anyone out there have any bright ideas?
Have you driven the car hard with the exhaust on it before? I know that the M5 driving experience M5's sound totally different from a stock one.
Wondering if the tone changed because there might have been some baffling that let go, hence causing a flow increase (setting off a SES light) and causing the drop in tone (lower restriction lower tone??)
This was covered in the past...I can't recall what was causing the problem but I think it was something to do with the VANOS or even the exhaust system.
Some people actually reported liking the new sound. What about you. Do you like it?
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Jason
Lighting Guru & Picture Poster Extraordinare!
'05 Range Rover w/mods
'05 K1200S w/mods
'07 997TT w/mods
Definitely a cam sensor issue. I had the same problem. The sensor alters the ignition timing, which affects power output and also the sound the exhaust makes. Have it fixed under warranty. Even though it's intermittent, they should be able to diagnose it from the stored fault codes, and trust me, it will eventually become full time.
I had the same problem on my old M5. I tried to get it diagnosed as a cam sensor, but they couldn't produce the right fault code. But I was certain that it was it.
'Rocket
__________________ 2006 Silver Grey on Indianapolis Red M5
Thanks all. Triflow, it is quite different than just driving hard. Atomic 80, I too like the sound, but I think it would set off a lot of car alarms. Thanks Keesdh, that thread is dead on, I appreciate it.
Will let you know what the dealer says, they called and said to bring the car in and that they had a BMW loaner for me to use in the interim.
Linear Mode
