m3 evo vanos question
Discussion
after reading a few posts on here and on other forums it seems to be that the m3 evo vanos units keeps breaking, can somebody please explain to me why this happens? How you can tell? what condition shorten its life? and how much it costs to replace?
sorry for all the q`s i`m daz and i`m new on here looking at buying a 98 e36 m3
cheers
sorry for all the q`s i`m daz and i`m new on here looking at buying a 98 e36 m3
cheers
i have had a s reg e36 m3 evo for about a year and no problem so far (touch wood) but went through the same thing as you before i decided to buy.
The vanos controls the valve timing and is a very clever peice of kit. From 0-3000 rpm (approx) it spins at one speed then increases speed to give better mid range torque. It works well but is fragile. There is as far as i know no way to predict when it will happen, as it just seems to go...
You will know when it happens as it will get stuck on one setting, either 0-3000 band or the 3000-7000 band. Basically this means that you will either accelerate fine but not mid range or v poor acceleration but normal after 3000 revs.
To replace costs about £1500 from bmw.
I suggest trying to find a car that has had it replaced and has a bmw warrenty on it, otherwise go for a car with 50k miles plus as apparently if it is going to go it will most likly go in the first 45k.
Hope that helps, otherwise great cars, brilliant fun and really enjoyed having mine.
>> Edited by tricky69 on Thursday 10th February 12:05
The vanos controls the valve timing and is a very clever peice of kit. From 0-3000 rpm (approx) it spins at one speed then increases speed to give better mid range torque. It works well but is fragile. There is as far as i know no way to predict when it will happen, as it just seems to go...
You will know when it happens as it will get stuck on one setting, either 0-3000 band or the 3000-7000 band. Basically this means that you will either accelerate fine but not mid range or v poor acceleration but normal after 3000 revs.
To replace costs about £1500 from bmw.
I suggest trying to find a car that has had it replaced and has a bmw warrenty on it, otherwise go for a car with 50k miles plus as apparently if it is going to go it will most likly go in the first 45k.
Hope that helps, otherwise great cars, brilliant fun and really enjoyed having mine.
>> Edited by tricky69 on Thursday 10th February 12:05
I have had a couple of BMWs now but im sorry to say never an M3 EVO, just 318is and now 328i Sport.
My friend has had many M3 Evos but we have only just been told what causes the Vanos unit to go wrong.
There is a little oil filter on the Vanos (Ithink at the front as you look at the engine, but dont quote me on that) which gets blocked.
BMW never change them on inspection services hence why the Vanos does pack up.
I am not sure what happens to the Vanos when it packs up, all i know is that it cost a fortune when it does.
The above imformation was given to me by Munich Legends.
Hope this helps.
My friend has had many M3 Evos but we have only just been told what causes the Vanos unit to go wrong.
There is a little oil filter on the Vanos (Ithink at the front as you look at the engine, but dont quote me on that) which gets blocked.
BMW never change them on inspection services hence why the Vanos does pack up.
I am not sure what happens to the Vanos when it packs up, all i know is that it cost a fortune when it does.
The above imformation was given to me by Munich Legends.
Hope this helps.
The Vanos is a cam phasing techique.
What happens is, a helical gear linkage allows the phase of the cam to alter by moving the linkage back or forward.
www.geocities.com/gkurka2001/CarTech/vvt_3.htm#Vanos
That site has a little diagram and explanation.
I see no reason why it would just "break". I assume if it goes, a seal might go, making it move between phases at random, which would be a bit rough, and perhaps damage the engine long term.
I'd say though, that more than likely it has a failsafe, and if a pump or something fails, then it just locks it at one end, and you'll just loose toruqe benefits across the range.
Dunno why it's so expensive to fix, it's just a pneumatically controlled diagphram really, that pushes or pulls the helical gears altering the phase.
Perhaps BMW like to do a good job and replace the cam chains and stuff while they are there, as all the timing stuff might get a bit damaged when all is not working right!
Hmmm
Dave
What happens is, a helical gear linkage allows the phase of the cam to alter by moving the linkage back or forward.
www.geocities.com/gkurka2001/CarTech/vvt_3.htm#Vanos
That site has a little diagram and explanation.
I see no reason why it would just "break". I assume if it goes, a seal might go, making it move between phases at random, which would be a bit rough, and perhaps damage the engine long term.
I'd say though, that more than likely it has a failsafe, and if a pump or something fails, then it just locks it at one end, and you'll just loose toruqe benefits across the range.
Dunno why it's so expensive to fix, it's just a pneumatically controlled diagphram really, that pushes or pulls the helical gears altering the phase.
Perhaps BMW like to do a good job and replace the cam chains and stuff while they are there, as all the timing stuff might get a bit damaged when all is not working right!
Hmmm
Dave
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