BMW's Valvetronic system. Reliable or issue prone?

I recently had the opportunity to go to the BMW plant in SC and do their Performance Driving School. I got to beat the living snot out of cars that I'll never be able to afford. Hell, they turned us loose on a 1 mile road course in a brand new M4 and M5. I've always liked BMW for being the drivers cars that they are, but never owned one due to fear (rational or not) of their reliability. I realize that the 2015 cars I drove are not the same as any BMW I can afford, but nonetheless the experience left me with a new found admiration for BMWs.

In my price range is the BMW 128i. Yeah, I know the 135i and E90 335i are out there, but I don't want to deal with turbo and/or direct injection. I want/need a car that's going to be as trouble free as I can get. I know BMW isn't Honda, I get it. I can live with that as long as it's not a total money pit. The 128i motor is a non-stressed naturally aspirated engine, therefore I would think it's less trouble prone. I know it includes Valvetronic valvetrain management. I don't know a ton about it. Is it a trouble spot for these motors? Teach me BMWs Valvetronic.

I've got two N52 motors, one in a 2007 Z4 3.0si with 98k miles, and another in a 2008 328xi that's pushing 118k miles. The Z4 has a three stage intake manifold that get's you 255 hp versus 225-230 in the 328.

I haven't had any Valvetronic issues in either of these cars. The only valvetrain associated feature is some pretty prominent lifter tick from time to time, which some high revs will generally help out.

The common issues with the motors are belt tensioners, which appear to last not much more than 60k miles (parts under $200, pretty easy to replace) and oil leaks at the valve cover and the oil filter adapter. I've avoided the former on both cars, had the latter on the 328.

These normally aspirated straight sixes are sweet, sweet motors as you rev them out...

Edit: For money, you can put the fancier manifold on your 128 and get the 255 Hp output

http://www.turnermotorsport.com/p-176947-n52-330-intake-manifold-software-upgrade-for-128i325i328i528iz4.aspx

I'm old school, but to me a proper BMW has a straight six, naturally aspirated engine, rear wheel drive, and a manual gearbox. Each generation has some piddly little things that go wrong that you have to keep after. They're flawed, but they have good bones.

As you said -- it's not a Honda, and that's not always a bad thing.

I think of the E46 as the last generation that you can work on, but people have been saying that about all of them for 20 years.

I find bmw to be the least scary of the german brands, from a reliability standpoint.

And by a wide enough margin, it would never cross my mind to be worried about a 128.

I'm looking at cars like the V6 Accord coupe 6spd and Altima 3.5SR coupe. Like them both, but the 128i can be had for a bargain these days. Just don't want to get into a money pit.

Here's a related discussion:

Buy a 128i thread

On Valvetronic, it seems to hold up fine. VANOS was a different story.

I've got an e61 with an N52. Just sprung a leak at the oil filter housing. Coming from playing with everything from an m10, m42, m52, the mechanical bits don't phase me. The biodegradeable wiring from the hella light units scare me more.

Only valvetronic thing I've changed that I remember is en eccentric shaft position sensor. It's really a pretty cool system. You just pull the valve cover to change the ESPS basically.

Worst part of 128s is the water pump and thermostat really. And if the cowl has EVER been removed, make damn sure it is reinstalled properly(there's a retainer that goes along the bottom edge of the glass that the cowl snaps into. It's common for this retainer to be tossed if the glass has been replaced by an inexperienced glass installer) or else water leaks.

All of the problems are well-documented and supported and when BMWs fail, they fail consistently.

Tyler H wrote: I'm old school, but to me a proper BMW has a straight six, naturally aspirated engine, rear wheel drive, and a manual gearbox.

I could not agree more.

Karacticus wrote: The common issues with the motors are belt tensioners, which appear to last not much more than 60k miles (parts under $200, pretty easy to replace) and oil leaks at the valve cover and the oil filter adapter. I've avoided the former on both cars, had the latter on the 328.

Have done plenty of the oil filter pedestal gasket/O-rings, and got to do one valve cover.

Kind of a neat setup, and by neat I mean WTF. It uses a metal gasket and aluminum bolts which are well and truly one time use. There are 22. I counted. Twice. The gasket leaked because some of the bolts were broken. The torque spec is silly, it is something like 4n-m plus 90 degrees. The bolts are not strong enough to accept 5 n-m of torque!

The valvetronic I cars (N62) will develop problems due to lack of roller bearings on the intermediate levers. The valvetronic II cars (N62TU) fixed those issues.

-Henry

I just bought a 328xiT, because my research confirmed the above. The N52 is reliable whereas the turbo and DI motors have way more power and fuel economy, but reliability is suspect.

By way of anecdote, my brother just spent $6k replacing both turbos on his '07 335xi.

Venture Team, assemble Ventronic!

Sorry. The last 20 time I've browsed past this thread, that's all I could think of.

Sorry to threadjack, but wow, I could have nearly written the OP's exact post.

I too very recently got to attend the M school. I too find myself looking at 128i's (not 35's for same exact reasons stated).

However, I do find myself drawn to the siren song of the M Coupe's. Actually registered on BAT but chickened out bidding on the red 99 coupe that is 11 hours away....aaaand drove an 07 m coupe at lunch today.

Problem I have in looking for 128i's is that it seems very rare to find one with sport seats which are high on my list. Plus I'd really like an LSD, but there is no JY swap option and aftermarket is steep. Kind of narrows the $ gap between a newer 128i and a higher mile clown shoe.

Anyway, everyone carry on with Valvetronic edification!