Leaky fuel injector pipe fitting

[chefinabox]

I replaced my spark plugs on my 2013 135i at 52k a few days ago and noticed what I believe is a small fuel leak in my 4th cylinder line.


I've never worked on high pressure lines before so I wanted to post here to get some input / suggestions:

1. What are good ways to diagnose this and next steps? Could it just be I need to tighten that fitting some?
2. I'm having trouble finding just that individual pipe. The dealer is saying they only sell the entire fuel rail system which is a route I really don't want to have to go.

[iminhell1]

That is absolutely a fuel leak.

DO NOT start or drive the car.

[iminhell1]

You can try to tighten the line. Don't go gorilla on it, just needs to be a healthy snug. Say about 14 ft/lb if I had to give a number to it.


Far as the parts go, looks like there is a date cutoff. up to 6/30/2013 and after. After looks to be an unservicable rail. Before being servicable.

The way your line looks to me, it's after and unservicable ... lines aren't available separate because they are welded at the rail. So if there is something wrong, you'd need a whole new setup ... salvage yard might be best $ option there.


There is the off chance that the line is tight and the problem is the injector seal is damaged. This can become a horrible situation and very expensive ... but judging by the fuel residue already there, the damage is done.

The seal is the bottom part numbers, 10 and 11:
http://bmwfans.info/parts-catalog/E8...injector_line/

If the line is tight to your satisfaction and not visibly leaking (engine has to be running to watch for leak, WARE EYE PROTECTION). Then listen for a rhythmic hissing from that injector and the smell of unburnt fuel. If you hear/smell that then it's a good chance the seal is damaged. Injector needs to come out and seal and decouple ring replaced.

[chefinabox]

Yeah, after looking again at where the pipe connects to the fuel rail I agree, that's one piece. My brain wanting that to be a separate pipe ignored the fact that's not a fitting and is welded to the rail. My vehicle was produced 2013-09-17 so that lines up.

[e36addict]

Yes, it's all one piece (the rail). Whoever did the valve cover job probably didn't torque it quite enough. Simple fix, and I've seen it a dozen times. Clean the dirty spot, put some torque on the line, and check for leaks. Easy.