I'm the guy with the Z4 35i as mentioned above.
I bought the car and have had to spend big money on it so far, So if you do get an N54 make sure you do your homework, I thought I did but I got taken by surprise with regards to a thing called waste gate rattle. That little rattle has turned my life upside down is all I can say. Mostly due to my mechanic that instead of fixing the bush that was worn like I asked had instead sent it to get done where they decided to strip my turbos and tell me that they were stuffed, This put me in a corner because we all know how these places to prove a point and make you spend more money if you tell them to put the turbo back together and return the car, your sure to get a car back with a newly ruined turbo that was fine before hand.
So I have had to buy 2x new turbos, plus labour etc has set me back close to 30k already, this did include tappet cover gasket and sump gasket and a service. I have also had to spend money on other bits and bobs here and there, all in all its cost me a hell of allot of money that i did not expect at all.
The after market warranty is useless they told me they wont replace the turbos or contribute towards them unless it breaks in two pieces. So don't rely on that.
Then there are the gasket problems on these cars, they are a common problem and will leak eventually.
If your injectors haven't been replaced they will need to be at some point and that's allot, the last price I heard was 27k incl labor and vat.
Then the High pressure fuel pump, not sure on the price of this but its allot.
The water pump, last price I got was R7.5k excluding labor to fit.
Then there is the carbon build up problem, need to find a trust worthy place to carbon clean your engine, this is SA so make sure you know where its going and find out if other people have had good experiences with them first.
Boost pipes cracking problem
Sump gasket leak problem
Oil housing gasket leak problem
I am not sure how accurate this is but as far as I know the earlier versions of these N54 motors 2006 - 2008 had a head gasket problem. I know my Dads 2008 E92 335i msport that had 68k on the clock had to have the head gasket replaced and that car was bone stock and my dad looks after his things like no bodies business. That was a 15k situation right there, he got the agents to do the job. Good idea that, I should have taken my car to the agents for the turbo replacement. Although in my defense I thought I was getting a waste gate bush replaced, no idea these clowns were going to strip my turbos down and tell me they worn. :smashScreen:
hmmm can't think of anything else right now but those are the major problems that can and will go wrong, so if you do get one have a look at the mplan history and make sure injectors, water pump and high pressure fuel pump have been replaced else make sure you got some bucks lying around.
Other than that, what an epic car to drive with some serious power and fun factor, well the Z4 35i is anyways, I have never driven a 135i before, I was told a long time ago that the suspension in them wasn't too great and they felt spongy around corners. This was by a guy with a 1M though so who knows how true that is as I'm sure the 1M is going to have far superior suspension and can't really be compared to the 135i.
