Different engines for the z4
Discussion
Hi, I'm looking to move on from my 320ci and get a z4, however after suffering through all the engine issues on my 320 I wanted to find out which of the early z4's have the best engine. As far as I understand 2005-2008 have different engines than the ones made in 2004 and earlier... Which of the z4 se models are the most reliable, what common issues should i look out for and just any general tips when buying one? Thanks 
Edited by Bobis on Wednesday 8th August 16:49
Early ones are the M54, not a bad engine but getting on now. They can drink oil, the odd head gasket and so on. 3.0 is 231 bhp. The later one is the N52, 258 bhp. They do go better, more economical etc - electric water pump failure, oil leaks and worst of all, the dreaded cam bearing ledge wear. That's almost enough to write off a Z4 now as the head cannot be repaired. A fairly rare fault but.....
Given the choice, a mint low mileage early car is the best bet - 231 bhp is enough really. When cars are as this age and value, you want to avoid £3000 bills ideally. Other Z4 stuff - make sure the hood works properly and check for any stiffness in the steering as electric column faults are $$$$$. That apart they're a good car and are basically an E46 underneath.
Given the choice, a mint low mileage early car is the best bet - 231 bhp is enough really. When cars are as this age and value, you want to avoid £3000 bills ideally. Other Z4 stuff - make sure the hood works properly and check for any stiffness in the steering as electric column faults are $$$$$. That apart they're a good car and are basically an E46 underneath.
Bobis said:
Thanks for the replies, so is looking for anything less than a 3.0l pointless? As far as I've seen people are saying anything less is just a detuned 3.0l
the detuned 3.0 is only on the very late 2007ish engines on cars badged z4 2.5si which have 218hp, the earlier z4 2.5 IS a 2.5l 192hp lump as found in e46 3series.the reason to go 3.0 is because in the real world they offer better performance at only a fractional difference in running costs to the 2.0/2.5
Pericoloso said:
helix402 said:
move the roof motor to the boot. Sorted.
Curious what that's about.Replacement units and labour rack up to 500-700 quid as well, unless you go to the nice guy on the Z4 forums who does what the guy above mentions, and relocates the motor into the nice dry boot, so no more failures.
NorthernSky said:
The motors sit in a water bath and rust out, then dramatically fail - like mine did, roof stuck down in a thunderstorm was NOT my Z's finest moment. :-)
Replacement units and labour rack up to 500-700 quid as well, unless you go to the nice guy on the Z4 forums who does what the guy above mentions, and relocates the motor into the nice dry boot, so no more failures.
I only ever wanted a Z4 Coupe, which meant I only had a choice of an N52 3.0Si or an M (I wish)! Replacement units and labour rack up to 500-700 quid as well, unless you go to the nice guy on the Z4 forums who does what the guy above mentions, and relocates the motor into the nice dry boot, so no more failures.
Despite the electric water pump issues I love the N52 engine (and I've paid for a replacement pump)
But it is rated at 265 bhp in a Z4 (258 bhp only seems to apply to early E90/E91 applications)!There are a few people on the z4forum who can revive and relocate roof motors for E85s for £100 or so around Bristol, Cheshire, Durham, Hook (Hants).
Just get one!
Gassing Station | BMW General | Top of Page | What's New | My Stuff