BMW E36 / E46 6 Cylinder Engines Why Do They Rev So Slowly

[KTMsm]

I recently bought a 325 Compact as everyone said they were fun

They lied

My main complaint is that below probably 5k it seems really lazy - is this due to a heavy flywheel or camshaft profile or something else ?

Essentially most japanese 4 cylinder engines are what I would call fun - they seem to want to rev and the BMW 6's just don't and I wondered how much I'd have to throw at one or whether it's an inherent characteristic ?

I don't recall my E36 328 being any better but I put that down to being strangled by design

[aka_kerrly]

Check the car has oem crank & cam sensors and clean the MAF+ air filter.

I've had a few i6 BMWs and 2 or 3 went flat and lost their zing when the cam and or crank sensor were playing up..never triggered fault codes.

[E-bmw]

I would also be checking the Vanos system as that can give the same effect along with uneven running, but they are normally a rev happy unit.

Didn't you test drive it first?

[Zener]

Something wrong with yours I run an M54 2.5 in an heavier touring and apart from being an absolute gem driven sedately it revs well to the red line with a notable step at 4 K RPM to redline

[Pica-Pica]

Never had a problem in 19 years and 150k miles on my E36 323i (2.5 6 cyl).
I used Shell V-plus (or whatever it was then); back then the price differential was sufficiently close to make the power increase and increased mpg worth it.

[Krikkit]

They have quite heavy DMFs which most revvy 4-cylinders won't have, but otherwise they seem about average. If yours is exceptionally slow then there's something wrong.

Post us a video and we should be able to tell you what's normal.

[The Wookie]

Vanos seals. If it's not been done already it will need doing on pretty much any M52 engine by now