BMW N54 Injectors leaking? Changing only the o-rings?

Ballistic · 10-13-2017, 03:47 AM

Don't do that. I will not tell you anything.
If you let the car sit for a long time, the leaked fuel will either evaporate or leak past the pistons where it breaks down the oil film on the piston,rings and cilinder wall. Car will start like close to normal.
These things operate at almost 3000psi when required. During cruising this is only about 600/700psi and after turning the engine off it will be under 300psi in no time. An injector might be leaking at one pressure but not at the other.

To test a leaking injector(s), Drive the car up to temperature, turn it off for 15/20min and then start it. If the injectors are leaking so bad that you need to do something about it, the engine will stumble upon starting.

Also; The injectors cannot by fixed without specialized equipment. Changing rings or high frequency cleaning does not help on piezo injectors. Trust me i tried... 3 times....

panchofarrera · 10-13-2017, 08:12 AM

Quote:

Originally Posted by Ballistic

Don't do that. I will not tell you anything.
If you let the car sit for a long time, the leaked fuel will either evaporate or leak past the pistons where it breaks down the oil film on the piston,rings and cilinder wall. Car will start like close to normal.
These things operate at almost 3000psi when required. During cruising this is only about 600/700psi and after turning the engine off it will be under 300psi in no time. An injector might be leaking at one pressure but not at the other.

To test a leaking injector(s), Drive the car up to temperature, turn it off for 15/20min and then start it. If the injectors are leaking so bad that you need to do something about it, the engine will stumble upon starting.

Also; The injectors cannot by fixed without specialized equipment. Changing rings or high frequency cleaning does not help on piezo injectors. Trust me i tried... 3 times....

Let me define what's happening. My car rarely ever "stumbles". Meaning, I don't usually see RPMs dropping or out of control except for rare mornings. What I am experiencing is a constant "hiccup" or mild misfiring on idle. Not strong enough to be visible in my RPMs but strong enough to be felt in my pedal and steering wheel.

jwebb335xi · 10-13-2017, 08:22 AM

Quote:

Originally Posted by 335e92tx

Quote:

Originally Posted by feuer

Let the car sit over hight with disconnected battery. In the morning first disconnect the fuel rail. If no flue sprays under pressure chances are you have leaking injector/s. Start removing the spark plugs. If you find spark plug with black sooth that smells like gas you found the leaking injector.

Yep, not a bad plan.. should be plenty residual pressure. and if there isnt there will likely be obvious signs of where it went.

Look for wet plugs too.

Ballistic · 10-13-2017, 08:34 AM

Your injectors are probably shot. You can check if they are leaking with the method in my previous post but it's also possible that the spray image has just become very bad and there is no consistent flow of fuel.
There is no way index 9 or lower injectors are still functioning properly at this time. My car had index 9's and they caused a lot of bad engine behavior. After replacing them with index 12's it's been running like a dream.

panchofarrera · 10-13-2017, 08:39 AM

Quote:

Originally Posted by Ballistic

Your injectors are probably shot. You can check if they are leaking with the method in my previous post but it's also possible that the spray image has just become very bad and there is no consistent flow of fuel.
My car had index 9's and they caused a lot of bad engine behavior. After replacing them with index 12's it's been running like a dream.

Ive seen a video where they diagnose this by pulling the injectors out, reconnecting them to the fuel rail pointing up and crank the engine to see which one sprays gasoline. Does this sound like a way to diagnose them?

335e92tx · 10-13-2017, 09:06 AM

Quote:

Originally Posted by panchofarrera

Ive seen a video where they diagnose this by pulling the injectors out, reconnecting them to the fuel rail pointing up and crank the engine to see which one sprays gasoline. Does this sound like a way to diagnose them?

The idea of highly atomized fuel spraying randomly for some reason causes me pause..

panchofarrera · 10-13-2017, 10:24 AM

Quote:

Originally Posted by 335e92tx

The idea of highly atomized fuel spraying randomly for some reason causes me pause..

Update: I just went outside and released the "pressure" from the fuel rail and found absolutely no pressure. No fuel came out after it sitting overnight with the battery disconnected. I will pull out every sparkplug later to look for fuel smell.

10-13-2017, 11:25 AM

Quote:

Originally Posted by panchofarrera

Ive seen a video where they diagnose this by pulling the injectors out, reconnecting them to the fuel rail pointing up and crank the engine to see which one sprays gasoline. Does this sound like a way to diagnose them?

YES.

Pull the LPFP fuse first though, obviously.

335e92tx · 10-13-2017, 11:48 AM

g/l

feuer · 10-13-2017, 11:50 AM

Quote:

Originally Posted by panchofarrera

Update: I just went outside and released the "pressure" from the fuel rail and found absolutely no pressure. No fuel came out after it sitting overnight with the battery disconnected. I will pull out every sparkplug later to look for fuel smell.

I have done this many times with success. I just did one. Cyl#4, 5 & 6 are most frequent, most frequent is cyl#6. (don't know why since cyl#5 works the hardest) Index #9 (from my experience) has the highest failing rate (you see a lot of refurbished index#9) I work on cars with unknown history so might be a link. I would stay away from index#9 just because of this.

feuer · 10-13-2017, 11:55 AM

Quote:

Originally Posted by panchofarrera

Ive seen a video where they diagnose this by pulling the injectors out, reconnecting them to the fuel rail pointing up and crank the engine to see which one sprays gasoline. Does this sound like a way to diagnose them?

You can do that (make sure they are unplugged) but why do all of that if you can pinpoint the (hypothetically) faulty injector by removing the spark plugs. Reinstalling the injectors with the old teflon seal might cause an issue that wasn't there! If you have new teflon seals (I see you called them 0-ring in the title) do it and replace them.

panchofarrera · 10-13-2017, 12:15 PM

Quote:

Originally Posted by feuer

You can do that (make sure they are unplugged) but why do all of that if you can pinpoint the (hypothetically) faulty injector by removing the spark plugs. Reinstalling the injectors with the old teflon seal might cause an issue that wasn't there! If you have new teflon seals (I see you called them 0-ring in the title) do it and replace them.

I just got done pulling the spark plugs. I took pictures of them which I will post later. Cylinder 2 had a stronger smell. Not sure if it is fuel.

Wolf 335 · 10-13-2017, 12:55 PM

I know injector cost is a bit steep for all 6, but I strongly urge you to change all six at once and be at peace.

Changing them individually or using rebuilt is a never ending chase and a headache.

335e92tx · 10-13-2017, 01:00 PM

Quote:

Originally Posted by Wolf 335

I know injector cost is a bit steep for all 6, but I strongly urge you to change all six at once and be at peace.

Changing them individually or using rebuilt is a never ending chase and a headache.

like clockwork, at least one or two will fail near 100K.. best to get rid of the entire set and get at least another 100 hopefully..

feuer · 10-13-2017, 01:25 PM

Quote:

Originally Posted by 335e92tx

like clockwork, at least one or two will fail near 100K.. best to get rid of the entire set and get at least another 100 hopefully..

How is this mileage (100K) dependent?

panchofarrera · 10-13-2017, 01:31 PM

So I found these:
https://rover.ebay.com/rover/0/0/0?m...2F222572216584

I know, I know. They are Index 9. However they are new and have a 2 year warranty. All 6 injectors for $250 vs. $1500 or more. Would you all go for it considering that warranty?

335e92tx · 10-13-2017, 01:36 PM

Quote:

Originally Posted by feuer

How is this mileage (100K) dependent?

you got me.. good German planning? ;-)

Just seen a few go south real close to that..

feuer · 10-13-2017, 01:46 PM

Quote:

Originally Posted by 335e92tx

you got me.. good German planning? ;-)
Just seen a few go south real close to that..

Not that because I work on cars, but let's take my own n54, build in 4/2008 (so not build in October lol), currently with 92k and 2nd replacement. Linking part failure, any part failure with certain mileage is absurd.

panchofarrera · 10-13-2017, 01:49 PM

https://m.ebay.com/itm/6-x-OEM-FUEL-...8/252425179529

Index 8, remanufactured with a 2 year warranty and shipped from the US, also included new seals and decoupling elements. How does that look?

feuer · 10-13-2017, 01:50 PM

Quote:

Originally Posted by panchofarrera

So I found these:
https://rover.ebay.com/rover/0/0/0?m...2F222572216584

I know, I know. They are Index 9. However they are new and have a 2 year warranty. All 6 injectors for $250 vs. $1500 or more. Would you all go for it considering that warranty?

yes, brand new with removed caps and no packaging, Made in Italy, shipped from China. Not that I'm biased, have purchased Chinese made products of great quality, but do yourself a favor and skip these. Index #12 are $115 each, or $690 total.

feuer · 10-13-2017, 01:54 PM

Quote:

Originally Posted by panchofarrera

https://m.ebay.com/itm/6-x-OEM-FUEL-...8/252425179529

Index 8, remanufactured with a 2 year warranty and shipped from the US, also included new seals and decoupling elements. How does that look?

https://www.fcpeuro.com/products/bmw...SABEgJWEPD_BwE
I have seen them sell for $115 each but for $130 with lifetime warranty is impossible to beat.

panchofarrera · 10-13-2017, 02:05 PM

I understand index 12 is the way to go. But I wont be able to absorb that cost anytime soon. And I don't want to damage my engine meanwhile.

The Index 8 come with new seals installed, decoupling elements and capped with an unlimited mileage warranty for 2 years. Is there a legitimate reason not to get these?

10-13-2017, 03:47 AM	#23
Ballistic Banned 127 Rep 123 Posts Drives: 335i E91 Join Date: May 2017 Location: NL iTrader: (0)	Don't do that. I will not tell you anything. If you let the car sit for a long time, the leaked fuel will either evaporate or leak past the pistons where it breaks down the oil film on the piston,rings and cilinder wall. Car will start like close to normal. These things operate at almost 3000psi when required. During cruising this is only about 600/700psi and after turning the engine off it will be under 300psi in no time. An injector might be leaking at one pressure but not at the other. To test a leaking injector(s), Drive the car up to temperature, turn it off for 15/20min and then start it. If the injectors are leaking so bad that you need to do something about it, the engine will stumble upon starting. Also; The injectors cannot by fixed without specialized equipment. Changing rings or high frequency cleaning does not help on piezo injectors. Trust me i tried... 3 times.... Last edited by Ballistic; 10-13-2017 at 03:53 AM..
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10-13-2017, 08:34 AM	#26
Ballistic Banned 127 Rep 123 Posts Drives: 335i E91 Join Date: May 2017 Location: NL iTrader: (0)	Your injectors are probably shot. You can check if they are leaking with the method in my previous post but it's also possible that the spray image has just become very bad and there is no consistent flow of fuel. There is no way index 9 or lower injectors are still functioning properly at this time. My car had index 9's and they caused a lot of bad engine behavior. After replacing them with index 12's it's been running like a dream.
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10-13-2017, 11:48 AM	#31
335e92tx ahat 1036 Rep 2,592 Posts Drives: Was '07-335e92 - Now '13-335IS Join Date: Mar 2008 Location: Texas iTrader: (6)	g/l __________________ '13 335IS N54 (1 of 373 LeMans Blue out of 3597 total production e92)- Grey interior (1 of 24 in LMB with any trans- 1 of 14 with DCT)-MODS -MFactory LSD/MHD-BQ custom Tune/ATM-IC/AFE Momentum GT Intake/Konis/Mfront&HeimJoint Rear rods&arms/Brembos. https://photos.app.goo.gl/Lo6aHZRo7XqtPkhL8
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10-13-2017, 12:55 PM	#35
Wolf 335 Brigadier General 2341 Rep 3,539 Posts Drives: 2007 E92 335i Join Date: Aug 2012 Location: GTA - Greater Toronto Area iTrader: (0)	I know injector cost is a bit steep for all 6, but I strongly urge you to change all six at once and be at peace. Changing them individually or using rebuilt is a never ending chase and a headache.
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10-13-2017, 01:31 PM	#38
panchofarrera Private 27 Rep 63 Posts Drives: 2008 BMW 335xi coupe Join Date: Oct 2017 Location: Lafayette LA iTrader: (0)	So I found these: https://rover.ebay.com/rover/0/0/0?m...2F222572216584 I know, I know. They are Index 9. However they are new and have a 2 year warranty. All 6 injectors for $250 vs. $1500 or more. Would you all go for it considering that warranty?
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10-13-2017, 01:49 PM	#41
panchofarrera Private 27 Rep 63 Posts Drives: 2008 BMW 335xi coupe Join Date: Oct 2017 Location: Lafayette LA iTrader: (0)	https://m.ebay.com/itm/6-x-OEM-FUEL-...8/252425179529 Index 8, remanufactured with a 2 year warranty and shipped from the US, also included new seals and decoupling elements. How does that look?
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10-13-2017, 02:05 PM	#44
panchofarrera Private 27 Rep 63 Posts Drives: 2008 BMW 335xi coupe Join Date: Oct 2017 Location: Lafayette LA iTrader: (0)	I understand index 12 is the way to go. But I wont be able to absorb that cost anytime soon. And I don't want to damage my engine meanwhile. The Index 8 come with new seals installed, decoupling elements and capped with an unlimited mileage warranty for 2 years. Is there a legitimate reason not to get these?
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