[Johndock23]

Hey guys, I just picked up an E90 335xi with only 32k on it. I want to begin modifying my car but looking to take a different approach than I'm used to. I know these cars have issue with the turbo wastegate and HPFP, so I want to be able to modify my car the most reliable way possible to avoid quicker fail of any parts. I know a tune, exhaust, and intake are inevitable, but I wanted to know any good upgrades to further enhance the reliability i.e. upgrading cooling system, intercooler, oil catch can etc. What are some upgrades to help here?

[xyaaeg234g234]

Get a walnut blast, new plugs and coils, find out what index your injectors are and possibly replace/upgrade them, charge pipe/dv/bov/downpipes can wait until you're pushing higher boost with a tune. check out the brakes/suspension and ensure all is in good working order. all i can think of at the moment - popular topic though so a bit of searching will help otherwise i'm sure many more will chime in shortly.

and as the forum members usually say - toss 5k into a 'fucked up N54 emergency' fund!

[csu87]

most reliable mod is a steering wheel cover. 2nd most are seat covers.

Everything else will put more strain on the car. Modding =/= reliable.

[2011z435is]

Originally Posted by csu87

most reliable mod is a steering wheel cover. 2nd most are seat covers.

Everything else will put more strain on the car. Modding =/= reliable.

Not really true... Things like a upgraded FMIC/intake/inlets/dps all will put less work on the engine and turbos and potentially make them more reliable, its only whenever you put on a aggressive tune and start making a lot more boost when you can hurt reliability.

[csu87]

Originally Posted by 2011z435is

Not really true... Things like a upgraded FMIC/intake/inlets/dps all will put less work on the engine and turbos and potentially make them more reliable, its only whenever you put on a aggressive tune and start making a lot more boost when you can hurt reliability.

sure if you keep it at stock tuning levels. But no one is going FBO and not looking to make more power.

[JasW]

Originally Posted by prodigymix

Get a walnut blast, new plugs and coils, find out what index your injectors are and possibly replace/upgrade them

Jeez, he said 32K, not 132K. Those are all nice, but he probably doesn't need any of that yet. Get MHD, put the stage 1 map on, and see if there are any misfires. If so, then replace the plugs, if not, carry on with the FMIC and DPs.

[AM330i]

Tune or not, if the injectors and hpfp are original, they will most likely fail. If the injectors are anything less than index 11 they will probably fail. I purchased my 08 535 a year ago with 60k and the pump was already shot and needed 6 injectors, 2 were definitely leaking and the rest I ended up replacing because I didn't want to deal with it once I put the jb4 on it. I would not suggest replacing them if you are not having problems, wait until they fail and then worry about. Put some money away now and save up for it when they do start failing.

[Captain Canuck]

An upgraded PCV valve and an oil catch can help reduce the amount of oil that go through the intercooler and charge pipe and burn up on the intake valves. When I started upgrading parts my intercooler and charge pipe were both coated in oil. You'll see people talking about walnut blasts to remove the carbon deposits on the intake valves from the oil that burns up on them. It can rob the engine of some power up top and cause misfires and rough idle. On a stock engine it’s not really a matter of if you will need to get it done but when, and where I live a walnut blast runs around $400 so reducing the frequency you need to clean the intake valves could save you money in the long run.

Some people have reported no oil issues after just upgrading the PCV valve (Rob Beck sells one for around $40) and some (myself included) have gone one step further and added an oil catch can. I poured about 30ml of oil out of my OCC last weekend while others never saw a drop of oil in theirs so YMMV. BMS sells a popular one that mounts near the firewall, I bought a Mishimoto one because it mounts at the front of the car where the air should be cooler and it’s more convenient to have a quick look to see if oil has collected. At the time I bought my OCC there was a thread where some people were complaining of oil seeping through the hoses of their BMS catch cans after prolonged use. It didn’t seem that the issue was ever addressed which also put me off a bit.

Some have gone a step further with dual catch cans (and more) but that’s beyond my level of expertise. You can find those discussions if you’re interested but the 2 above are the most common fixes for N54 oil problems.

As others have mentioned catless downpipes, an upgraded FMIC and inlets and outlets have their place in reducing turbo backpressure, keeping intake air temps down and decreasing turbo wastegate duty cycle. An upgraded metal charge pipe is a good idea if you plan to increase boost pressure as the stock plastic charge pipe can either pop off or break. Some have had issues at stock boost levels while others have run the stock pipe at much higher levels without any problems so again YMMV.

[Johndock23]

Thanks for the input guys, that's very helpful. My goal is put a few bolt ons and upgrade some parts to allow better airflow to prolong the life on the turbos and any other components related to them. I'm NOT looking for 500-600 hp but more of a conservative tune and upgrades to also be reliable. I don't race just an enthusiast looking for a little bit more power and sound. How often should I do the Walnut Blasting? Are there any recalls on the HPFP or Injectors or Turbos? Thanks.

[Johndock23]

Originally Posted by JasW

Jeez, he said 32K, not 132K. Those are all nice, but he probably doesn't need any of that yet. Get MHD, put the stage 1 map on, and see if there are any misfires. If so, then replace the plugs, if not, carry on with the FMIC and DPs.

Do you prefer MHD over JB4 and COBB? Is one more reliable then the others? Cheaper?

[JasW]

Originally Posted by Johndock23

Do you prefer MHD over JB4 and COBB? Is one more reliable then the others? Cheaper?

MHD all the way. If you're just getting into tuning, it's the only logical choice. It has far outstripped Cobb in a number of ways, not the least of which are support for its stock maps and sheer convenience. So there's no point in even considering Cobb, unless perhaps someone gives you an Accessport for free.

As for JB4, there are some who contend that MHD with a JB4 backend flash is the best of both worlds, while others contend JB4 (at least by itself) affords inconsistent power. Regardless, you're not going to find all that many people who get MHD and then get a JB4. Most already had a JB4 when MHD hit. MHD alone is more than sufficient. It's also the cheapest option, particularly if you already have an Android device. (All three options are reliable.)

[Johndock23]

Originally Posted by JasW

MHD all the way. If you're just getting into tuning, it's the only logical choice. It has far outstripped Cobb in a number of ways, not the least of which are support for its stock maps and sheer convenience. So there's no point in even considering Cobb, unless perhaps someone gives you an Accessport for free.

As for JB4, there are some who contend that MHD with a JB4 backend flash is the best of both worlds, while others contend JB4 (at least by itself) affords inconsistent power. Regardless, you're not going to find all that many people who get MHD and then get a JB4. Most already had a JB4 when MHD hit. MHD alone is more than sufficient. It's also the cheapest option, particularly if you already have an Android device. (All three options are reliable.)

Is MHD through the OBD? Unfortunately, I don't have an Android device, would I have to get one to have this work. I am reading up on MHD and still don't quite understand it. Do you have the tune for your car now?

[JasW]

Originally Posted by Johndock23

Is MHD through the OBD? Unfortunately, I don't have an Android device, would I have to get one to have this work. I am reading up on MHD and still don't quite understand it. Do you have the tune for your car now?

Yes, through the OBD port, and it's Android only because of the iPhone's self-imposed limitations. Inexpensive (~$50) Android tablets work fine, though. There is some info on them in the main MHD thread, although you might have to dig to find it due to the size of the thread. I have a custom MHD map from a third party tuner on my car right now. The first MHD tune I had was the stage 1 map offered directly by MHD.

[Johndock23]

Originally Posted by JasW

Yes, through the OBD port, and it's Android only because of the iPhone's self-imposed limitations. Inexpensive (~$50) Android tablets work fine, though. There is some info on them in the main MHD thread, although you might have to dig to find it due to the size of the thread. I have a custom MHD map from a third party tuner on my car right now. The first MHD tune I had was the stage 1 map offered directly by MHD.

Thank you, I've made up my mind I will try the MHD stage 1 for now. From what I read, It looks like BMW recommends changing the plugs every 45k. How often should you walnut blast the engine? How long do the fuel injectors last? I'm not sure if I should get these parts done before I tune, because my car only has 32k on it right now.

[JasW]

Originally Posted by Johndock23

Thank you, I've made up my mind I will try the MHD stage 1 for now. From what I read, It looks like BMW recommends changing the plugs every 45k. How often should you walnut blast the engine? How long do the fuel injectors last? I'm not sure if I should get these parts done before I tune, because my car only has 32k on it right now.

Check out the info at the top of the First Time Tuners thread here in the forum. It wouldn't be a bad idea to get new plugs, but you may not actually need to at this point.

[Jeff@TopGearSolutions]

Walnut blast every 35K ideally. Minimum every 50K for optimum performance.

Spark plugs every 25K when tuned.

For peace of mind and the utmost in reliability consider 6 new injectors, index 12 revision.

Also inspect your valve cover for leaks or cracks. Prone to crack around 45K miles for some.

FMIC is the first recommendation after a tune. That helps keep the engine and turbo's happy.

Also you'll want a charge pipe as those are prone to crack once tuned and as they age.

[B.M.W.]

A charge pipe+BOV, a better intercooler, RB PCV valve+Cap, Steering wheel cover and the felt for the Windows (prevent scratching).
I'd also recommend upgrading your brake pads to low dusting pads and higher temp brake fluid when you need to flush it.


A walnut blast+Plugs would be good about 50k miles.

[Johndock23]

Originally Posted by Jeff@TopGearSolutions

Walnut blast every 35K ideally. Minimum every 50K for optimum performance.

Spark plugs every 25K when tuned.

For peace of mind and the utmost in reliability consider 6 new injectors, index 12 revision.

Also inspect your valve cover for leaks or cracks. Prone to crack around 45K miles for some.

FMIC is the first recommendation after a tune. That helps keep the engine and turbo's happy.

Also you'll want a charge pipe as those are prone to crack once tuned and as they age.

Great, thank you. I read on here that the 08 models have strong charge pipes then later models? And what's in install like on FMIC? Any certain brands you recommend? Do you need a different tune for a FMIC?

[jaymesbry]

Originally Posted by Johndock23

Hey guys, I just picked up an E90 335xi with only 32k on it. I want to begin modifying my car but looking to take a different approach than I'm used to. I know these cars have issue with the turbo wastegate and HPFP, so I want to be able to modify my car the most reliable way possible to avoid quicker fail of any parts. I know a tune, exhaust, and intake are inevitable, but I wanted to know any good upgrades to further enhance the reliability i.e. upgrading cooling system, intercooler, oil catch can etc. What are some upgrades to help here?

Do you know what has been replaced on it so far?

Great job getting a car with that low a mileage!

As for now, I would try to drive it as much as possible. With a car that old with such low mileage, maybe some of the rubber bits and hoses have decayed over time.

The original parts were the disaster on these cars, obviously over exaggerating but yea.. so the only thing I am worried about is that you're on the earliest revisions on these things and now they may fail when you're out of those extended BMW warranties

But obviously starting with MHD will show you all the weakness a lot sooner so go for it!

The intercooler is always a great bet as well. It really just depends on how much power you're going to run, How much do you want to cut the front bumper, and if you care about it looking stock or not. But read the super long intercooler thread on here, lots of suggestions for intercoolers!

Good luck and welcome

[Tiago@VRSF]

Another idea, anything that will reduce WGDC like a free flowing intake/inlets or a larger less restrictive intercooler/downpipes will increase the life of the turbos since they can operate at lower wheel speeds.

[Johndock23]

Originally Posted by jaymesbry

Do you know what has been replaced on it so far?

Great job getting a car with that low a mileage!

As for now, I would try to drive it as much as possible. With a car that old with such low mileage, maybe some of the rubber bits and hoses have decayed over time.

The original parts were the disaster on these cars, obviously over exaggerating but yea.. so the only thing I am worried about is that you're on the earliest revisions on these things and now they may fail when you're out of those extended BMW warranties

But obviously starting with MHD will show you all the weakness a lot sooner so go for it!

The intercooler is always a great bet as well. It really just depends on how much power you're going to run, How much do you want to cut the front bumper, and if you care about it looking stock or not. But read the super long intercooler thread on here, lots of suggestions for intercoolers!

Good luck and welcome

Thank you, I saw this E90 335xi in a 6 MT and it happened to be my favorite color (Monaco Blue) with only 32k on it and I knew it was the right car. All I know is that the brakes pads and rotors were done, tires, and an oil change. The in service date of the car is 6/02/08 so the turbo extended warranty is over but the HPFP is still active (120,000k/10 years) I am sure I will need to do a tune up soon. From what I understand about the previous owner of my car, is that it was used as a commuter car to get to the train station and whatnot, and probably spend a lot of time in a parking garage. There is zero rust and the under-carriage of the car looks brand new. I recently replaced the stock intake with BMS DCI and then went through to check all the hoses I could see, seemed to be in really good shape (love the intake BTW). I just bought the d+kcan cable from a member on here and whenever that comes in I will do the MHD flash. I believe the map Pack for stage 1 comes with stage 1+ incorporating FMIC. If so that would work great! I am not looking for a ton of power, 400-450 would do just fine as I will not be racing or burning rubber on this car. Just something with a little more pick up (as I know these N54's are known to unleash) and more breathing room for the turbos for hopefully more life. I'll check the FMIC thread, but would like to keep the car looking stock in that regards and would like the least bumper modifications. And thanks again, I truly love this car and I've had many. I've had cars like the new WRX and had a B8.5 S4 but nothing feels like the way my E90 does and the Turbos are fantastic (more of a turbo fan then a supercharged fan, due to the types of modifications and sheer sound). I'm really looking forward to beginning this project and will have this car for a long time. All the input has been great, really appreciate it.

[pits200]

Reliable and N54 should never be placed in the same sentence unless you're saying, "The n54 is extremely reliable at having problems"