Thinking of getting a N54 135i, questions re what to look for, mods and maintenance

[Daemos]

Looking to move away from my MY02 STI by the end of the year once I've finished it. Want to move into something more comfy, newer and has the potential to make similar power with just bolt ons + tune (so no changing turbos, no engine internals etc)

This puts the N54 135i (in MT) at the top of my list, considering they are becoming quite affordable now as well.

What should I look for when l start looking? Any issues to be aware of?

What are some things that need to be done for reliability, it seems like oil cooler, FMIC is necessary for Australian summers to keep oil and air temps reasonable.

Any way to prolong the life of the injectors? It seems strange they are a wear and tear item, as I've never ever in my life had fuel injectors fail on me, and they have only been changed to go with bigger injectors.

How is the running costs of the car? FWIW my gf owns a E46 325i, and it's cheaper to run than my STI is.

Any way to run flex fuel on the car? My STI through the OEM ECU, opensource firmware and a flex fuel sensor can have full flex fuelling capabilities, which means you can add whatever ratio of ethanol, the ECU will know the level of ethanol and automatically adjust timing and boost to match that level of ethanol.

I'm unfamiliar with BMW servicing, for the E46, based on the dashboard, there are 3 levels, oil change, service I and service II. What is checked/ replaced during those, and what else should be replaced at major intervals say for example, belts, fuel filter, etc...

Any mods you recommend as a must do?

Thanks for taking the time to answer my questions!

[titium]

injector failures are down to design and from that I can tell primarily effected 07,08 model cars the newer injectors are much more reliable but that's not to say that 09+ won't get an injector failure just much less common. (there was a voluntary recall for some of the older failure prone injectors)

also look (or listen) out for wastegate rattle particularly on high km cars which will end up requiring turbo replacement (also more common on earlier model cars)

the n54 requires cleaning of the intake valves at approx 80k km at a cost of 500ish. other then that waterpumps seem to go around 80-120k km.

aftermarket oil cooler only required for track use and even then plenty of people use the stock oil cooler.

[Daemos]

Thanks for the reply! I'd be looking at MY10 (I believe the last of the N54s)

What causes the wastegate rattle? Any youtube videos? I'm guessing the wastegate isn't secure, so it opens up, leaking boost, causing the turbos to over spin, and fail?

The intake valve cleaning is the walnut blasting right? that's not too bad cost wise...How much is the water pump? 80-120k km doesn't sound too bad for a water pump.

[titium]

few guys have put up with the rattle for a while but eventually you will need to change turbos. plenty of info on here and videos on YouTube of it. seems to mainly effect older model cars and/or high mileage cars 150k km+

yep intake and walnut blast are the same

[titium]

oh and be prepared to replace the chargepipe common on 09+ cars due to a slightly different design.

mine broke on stock boost. think it cost me 400ish for an aftermarket metal one.

[Daemos]

I searched some youtube videos, some people seem to state that tightening or the adjustment of the wastegate arm is the solution for the wastegate rattle. Wonder if that's the case.

Might be a possibility to have the OEM wastegates welded shut and run external gates

[titium]

don't think it's as easy as that as it would have been done already.

most people use it as an excuse to upgrade turbos

[vtl]

Originally Posted by Daemos

I searched some youtube videos, some people seem to state that tightening or the adjustment of the wastegate arm is the solution for the wastegate rattle. Wonder if that's the case.

Might be a possibility to have the OEM wastegates welded shut and run external gates

You can only adjust the rear turbo from underneath the car. The front turbo needs to be completely removed from the car to adjust. The labour to remove the turbos is quite extensive, most people would just upgrade the turbos.

Running external gates would be too much work when you can just upgrade your turbos.

The rattling wastegates are caused by a number of factors. Could be a simple vacuum leak, worn wastegate flapper bushing or wastegate arm wear.

[The Wind Breezes]

Originally Posted by Daemos

Might be a possibility to have the OEM wastegates welded shut and run external gates

lmao. that's NOT gonna happen.

[Daemos]

Okay... If I need to change the turbos... Who can tune the ECU.. I'm talking about flash tuning.

[The Wind Breezes]

You know, I thought there was extended factory coverage on the wastegate rattle?

Also, you say you don't want to put on a nonstandard turbo, so if you replace the turbos with factory you'll be good to go and can use standard tuning.

[vtl]

Originally Posted by Daemos

Okay... If I need to change the turbos... Who can tune the ECU.. I'm talking about flash tuning.

Get MHD, its an app on android that you can upload flash tunes. You can either get a dyno tune or remote tune. Not many people in Aus who are familar with these cars and can dyno tune. Remote tune you get a base tune and send them back the logs of some pulls and they refine the tune for you. Over a few interations it gets dialed in. Has its pros and cons.

Originally Posted by The Wind Breezes

You know, I thought there was extended factory coverage on the wastegate rattle?

Also, you say you don't want to put on a nonstandard turbo, so if you replace the turbos with factory you'll be good to go and can use standard tuning.

No extended warranty in Australia

[Daemos]

Originally Posted by vtl

Get MHD, its an app on android that you can upload flash tunes. You can either get a dyno tune or remote tune. Not many people in Aus who are familar with these cars and can dyno tune. Remote tune you get a base tune and send them back the logs of some pulls and they refine the tune for you. Over a few interations it gets dialed in. Has its pros and cons.

Yeah MHD is the plan. If the turbos fail, I'd rather have the opportunity to invest in turbos that won't fail...

[dh58]

You don't NEED to change your turbos.

I have the rattle and it comes an goes. It doesn't affect performance.

Yes it is a little annoying at times but as I said, it comes and goes and there are ways to minimize it.

Really the only thing you need to worry about is the HPFP and injectors. Even those can be purchased cheaply online. Everything else is regular maintenance anyway.

Just do this:
Jb4
MHD
downpipes
stage 2 lpfp
E85 fuel

If you want..
Chargepipe
Intake

You'll have a weapon

[Daemos]

Originally Posted by dh58

Just do this:
Jb4
MHD
downpipes
stage 2 lpfp
E85 fuel

You'll have a weapon

Is the JB4 required if the MHD can do flash tuning? Also There is no true flex fuel setup for the N54 or N55, correct? If so, then E85 isn't for me, unless if I can live in a place where E85 is abundant and 100% within E85-90, which I do not live any United E85 stations. If I don't use E85 do I need the low pressure fuel pump upgrade?

[OzJustin]

Originally Posted by Daemos

Is the JB4 required if the MHD can do flash tuning? Also There is no true flex fuel setup for the N54 or N55, correct? If so, then E85 isn't for me, unless if I can live in a place where E85 is abundant and 100% within E85-90, which I do not live any United E85 stations. If I don't use E85 do I need the low pressure fuel pump upgrade?

Most people running ethanol are doing blends in the 30-60% ethanol range from what I've seen. If you're happy with a 98RON map then no need for an upgraded low pressure fuel pump. Just make sure your existing fuel and spark setup is running reliably before tuning. You can still see 250rwkw+ comfortably with no ethanol.

[vtl]

Originally Posted by Daemos

Is the JB4 required if the MHD can do flash tuning? Also There is no true flex fuel setup for the N54 or N55, correct? If so, then E85 isn't for me, unless if I can live in a place where E85 is abundant and 100% within E85-90, which I do not live any United E85 stations. If I don't use E85 do I need the low pressure fuel pump upgrade?

No need for JB4. The only notable features you will miss out on is map switching and instrument cluster boost gauge.

No true flex fuel tuning for N54, its quite primitive compared to evos and wrxes. Will be quite some time before its at the same level, but at least its being actively developed.

If you don't use E85 you don't need an upgraded fuel pump unless you upgrade your turbos.

[The Wind Breezes]

Good flash tune has much better driveability than JB4.

As an aside, it's pretty pathetic that 8 years on there's no map switching via software on flash tunes for N54. Other cars with ecus that are JUST AS COMPLEX (MED17) have had this feature for forever.

[titium]

don't mean to highjack the thread but should be useful for the OP. what tune and supporting mods would you guys recommend I'm in the market for one. car is currently stock minus charge pipe. looking to run straight 98 as a daily drive.

[vtl]

Originally Posted by titium

don't mean to highjack the thread but should be useful for the OP. what tune and supporting mods would you guys recommend I'm in the market for one. car is currently stock minus charge pipe. looking to run straight 98 as a daily drive.

This is what I'm running:

MHD Stage 2
Wagner EVO1 performance intercooler
AP Downpipes
Drop in BMC panel filter into stock airbox
Turbosmart Kompact plumb back diverters

Walnut blast will also pick up a little more power in the mid range and high rpm depending on how caked your valves are at the moment.

I think its plenty powerful. Would definitely need to upgrade some suspension parts to enjoy it fully. Rear subframe bushings at a minimum, LSD is really needed at this power level. Can't believe some people run upgraded turbos on stock suspension!

[7smurfs]

Originally Posted by titium

don't mean to highjack the thread but should be useful for the OP. what tune and supporting mods would you guys recommend I'm in the market for one. car is currently stock minus charge pipe. looking to run straight 98 as a daily drive.

If you already have charge pipes then:

Tune: MHD/JB4

Exhaust: DPs

Intake: DCI

Cooling: FMIC

Then you should be FBO status

[Daemos]

Originally Posted by OzJustin

Most people running ethanol are doing blends in the 30-60% ethanol range from what I've seen. If you're happy with a 98RON map then no need for an upgraded low pressure fuel pump. Just make sure your existing fuel and spark setup is running reliably before tuning. You can still see 250rwkw+ comfortably with no ethanol.

Yeah 250rwkw would be okay as long as it's a lower reading dyno...haha I've seen upto 20% differences between dynos of the same brand and model depending on setup, ramp rate and calibrstion. My sti once fully tuned on 98 should be around the 250-260kw atw mark on a lower two to normal reading dyno dynamics dyno...and around the 280-300kw atw mark on full e85 and full boost between 3700 rpm-3900rpm holding all the way to 8000rpm.