[Mark e90]

Hey guys, Im thinking of yet again returning to an e90 ( i don't know why i ever move away ! ), anyway I'm actually looking at an e92 for a change and would like 330i or 325i but for my price range its on the change over from the n52 to n53. i can see that the n53 has slightly better performance and mpg figures but is it as good an engine as the n52 for reliability ? or is the n53 just as good ?

the n53 seems like the best bet for myself with mpg figures almost matching the diesel models and still decent performance.

Look forward to you guys input and i may possibly be on here soon but not jumping in to quick this time, biggest regret with my old e90 was it was auto and i need a manual iv not had a manual car for 5 years ! although even in the uk manual bmws seem to be a dying breed

[Efthreeoh]

Being from the States, we never got the N53. But my research tells me it had direct injection (where as the N52 does not). My concern with direct injection on the N53 is the same as the N54/55 carbon build up on the valves.

[Delta0311]

Carbon build up is mainly a n54 issue. I have an n55 with about 46k on the clock. Had a buddy of mine do my ofhg about 1 or 2k miles ago. While he did that I had him check my valves and there was hardly any build up. Meanwhile when another one of my friends had a 08 335, he had to get the walnut blasting at about 50k because the valves where badly gunked up. Cannot speak for the N53 but I don't think it will be as much of an issue as it is on the N54.

[Efthreeoh]

I think the general issue with direct injection is if the oil separator is not engineered well, carbon buildup is an issue since the detergents in the fuel doesn't get on the valves. But since the N53 wasn't in the US, us yanks have no history with it. Maybe the N54's higher intake pressures exacerbate the issue.

[Saintor]

The N53 272HP 330i is a great achiever. Reported fuel economy is vastly improved compared to the N52. However I would be hesitant because of maintenance. These engines work with very high pressure gas system... I don't know if they have carbon deposits issues as well.

[smuler]

If it's best for you, go for N53. Focus on getting a low mileage manual M Sport in colour and spec you want; won't be easy as they are rare in manual form here. Then thoroughly check cars history. You can always get a warranty (from BMW) to cover unreliability concerns. But don't let concerns put you off. I didn't with my 335i and it's been very reliable.

[Taskmaster]

The N53 has a few more HP (supposedly even when tined) but I'll stick with the reliable N52.

[techietaichi]

Originally Posted by TheAxiom

The N53 has a few more HP (supposedly even when tined) but I'll stick with the reliable N52.

Yep, same here. My gal is 9 years old(I've owned her for 3), she's sitting on 135K and I've clocked over 80K by myself, as I've a long commute each day. Outside of regular maintenance items, there's been no problems whatsoever. I'm like this, if I can't own a car without having a warranty(which I think is a total scam anyways), I'll pass. She ain't much for power and she ain't the prettiest out there, but she makes me plenty happy.