[mcp]

hey everybody i was doing my valve cover and said screw it and took out my spark plugs to see how they were looking after about 8k miles.

to my dismay, 2 were blacked out and 1 was wet and smelled faintly of fuel. [IMG]https://ibb.co/kHZVMnJ[/IMG] Ive been having a slight decrease in MPG, and occasional rough warm start ups.

These are on cyl 2 and 5, and all of my injectors are index 10. Car is '09.

1. is there any way to strictly confirm they are leaking

2. what is the cheapest way to fix these

3. why do i see form posts about buying a set for $1000 but they're over $2000 on fcp

[Dave92N54]

1. You've got it. Your blacked out plugs are on cylinders with leaky injectors.

2. Don't cheap out here. You will only have problems. Only "cheap" injectors i'd maybe trust would be the reman ones from FCP.

3. Injector prices have been rising for awhile. They used to be I believe as cheap as $800 a set at one point. I got mine for $1200, 2 years ago.

[Saif2018]

Originally Posted by mcp

hey everybody i was doing my valve cover and said screw it and took out my spark plugs to see how they were looking after about 8k miles.

to my dismay, 2 were blacked out and 1 was wet and smelled faintly of fuel. [IMG]https://ibb.co/kHZVMnJ[/IMG] Ive been having a slight decrease in MPG, and occasional rough warm start ups.

These are on cyl 2 and 5, and all of my injectors are index 10. Car is '09.

1. is there any way to strictly confirm they are leaking

2. what is the cheapest way to fix these

3. why do i see form posts about buying a set for $1000 but they're over $3000 on fcp

What you described is the symptoms of leaking injectors.

There's only one real solution and that's to replace them with new ones, Index 12 preferably.

No one is selling 6 x new Index 12 for $1000,

[mcp]

is buying two used under index 10 injectors viable?

i don't have $600 for two index 12s much less the $2000 for six because you're supposed to do them in banks and my leaking ones are in both banks.

[BSM n54iS]

Maybe swap some injectors around and just get 3 new ones..? Should prolly code all 6 though to be sure if you did that but I don't think that would be a problem

[Saif2018]

Originally Posted by mcp

is buying two used under index 10 injectors viable?

i don't have $600 for two index 12s much less the $2000 for six because you're supposed to do them in banks and my leaking ones are in both banks.

Yes of course you could try that,

[tej98]

Originally Posted by mcp

is buying two used under index 10 injectors viable?

i don't have $600 for two index 12s much less the $2000 for six because you're supposed to do them in banks and my leaking ones are in both banks.

If you need, I'm fairly certain you can just change each leaking injector at a time and mix index in banks. I'm pretty sure iqraceworks has been doing this with no issues so far, so that is another option as well.

TBH I was planning on doing them all in banks at a time, but with the recent price hike I'll be doing them one at a time on the last bank I have left unless I find a good deal on a used set.

[TheMidnightNarwhal]

Originally Posted by tej98

If you need, I'm fairly certain you can just change each leaking injector at a time and mix index in banks. I'm pretty sure iqraceworks has been doing this with no issues so far, so that is another option as well.

TBH I was planning on doing them all in banks at a time, but with the recent price hike I'll be doing them one at a time on the last bank I have left unless I find a good deal on a used set.

I also only replaced one and no issues yet.

[Jorow99]

Swap injectors so you have one good bank then replace the other bank with used index 12s

[iqraceworks]

Originally Posted by tej98

If you need, I'm fairly certain you can just change each leaking injector at a time and mix index in banks. I'm pretty sure iqraceworks has been doing this with no issues so far, so that is another option as well.

TBH I was planning on doing them all in banks at a time, but with the recent price hike I'll be doing them one at a time on the last bank I have left unless I find a good deal on a used set.

Yep....no issues with different index injectors in the same bank as long as you code them in correctly. My car had index 1's and index 7's when I got it. One of the index 7's was leaking so I replaced it with a new index 12. I've been running it that way for a couple of years now...no issues, logs look great, and even with bigger turbos on an E40 custom tune...no fueling issues at all.

I know BMW says not to mix index 12's with anything under an index 10 (or maybe 11?), But lots of people do it....and I've never heard anyone report any type of problem...not a single person.

As far as replacing injectors....I would never roll the dice on used ones, for all you know they could be leaking too. Just buy a brand new one from FCP....yes, they are expensive...but it is what it is. It sure is cheaper than rebuilding your motor after your leaky injector saturates your oil with fuel and caused your rod bearings to fail.

[Sp3ctr35tatus]

I would definitely check out Straight Six Autoparts, they have some very decent prices on index 12s. They're used but generally are very reputable dismantler.

[Jaronbwall]

Do people have success ultrasonically cleaning leaking injectors? I watched a YouTube video about this and it leads you believe it fixed the leaking injector. It wasn't a bmw specific injector though.
A friend of mine has a cleaning system that he uses for parts and sport bike stuff.

[TheMidnightNarwhal]

Originally Posted by Jaronbwall

Do people have success cleaning leaking/faulty injectors? A friend of mine has an ultrasonic cleaning tank that he uses for clean parts.

Cleaning definitely won't help with leaking. Only if your issue is poor spraying or things like that.

[Jaronbwall]

Originally Posted by TheMidnightNarwhal

Cleaning definitely won't help with leaking. Only if your issue is poor spraying or things like that.

So it's an internal/mechanical issue then. I figured cleaning doesn't work since nobody mentions it in the forums. YouTube... just trying to sell expensive tools that don't fix the problem. I'm running a mixed set of index 7 and 9's if I remember so knock on wood they continue holding up!

[Saif2018]

Originally Posted by Jaronbwall

So it's an internal/mechanical issue then. I figured cleaning doesn't work since nobody mentions it in the forums. YouTube... just trying to sell expensive tools that don't fix the problem. I'm running a mixed set of index 7 and 9's if I remember so knock on wood they continue holding up!

Can confirm cleaning doesn't work, tried it using so called DI injector cleaning. Don't know any N54 owner who has fixed any leaking injectors through cleaning ultrasonic or otherwise.