Injector leak?

Woodrobin

Veteran Member
Joined
Jun 21, 2010
Location
Topeka, KS
TDI
2001 Jetta GLS
I have what I think is an injector leak. Three of them - dry as a bone. The fourth (first from the left as I face the engine) looks like this:



The fuel seems to be leaking out near where the metal pipe attaches. From other related threads I've looked into, it seems there's some hope that tightening, or unscrewing and rethreading, the nut might get things back in proper order. Any suggestions or ideas as to what might be causing this and what I can do to fix it are more than welcome.

Full disclosure: I recently switched from a 20% biodiesel blend (dipping to about 10% due to a top-off with regular diesel in the dead of winter) to 100% biodiesel. I don't know for certain whether the timing is close between the switch and the leak, as I didn't notice the leak until small amount of fuel ended up on my driveway (about 1-2 inch spots, a half dozen or so). I'm also not clear on how or why it might be connected, but didn't want to leave out anything. And yes, the engine cover is now going to take up semi-permanent residency in the garage. :mad:
 

KLXD

Top Post Dawg
Joined
Aug 22, 2009
Location
Lompoc, CA
TDI
'98, '2 Jettas
Yes, try backing the nut off a bit and retightening.

Could also be that return hose or the rubber cap.
 

JASONP

Top Post Dawg
Joined
Feb 24, 2008
Location
Guelph
TDI
2015 Golf TDI Comfortline 6spd
also replace the fuel return lines to the pump, they look a little leary of a tight seal
 

Woodrobin

Veteran Member
Joined
Jun 21, 2010
Location
Topeka, KS
TDI
2001 Jetta GLS
also replace the fuel return lines to the pump, they look a little leary of a tight seal
Those were replaced August 21, 2010 by CoolairVW, but I'll certainly take a look at them. I assume folks like BleachedBora or idparts would have those lines?
 

Woodrobin

Veteran Member
Joined
Jun 21, 2010
Location
Topeka, KS
TDI
2001 Jetta GLS
I ended up tracking the leak down definitively to the fuel injector return lines, and replaced them with Viton flouro-elastomer lines that are guaranteed non-reactive with, and non-porous to, biodiesel. Here is a link to a post with pictures of the process and more information.

And an exposed nipple shot, just because I can:



Now aren't you glad I was talking about the engine? :D
 

bhodgkiss

Veteran Member
Joined
Sep 11, 2006
Location
Banbury, UK
TDI
AFN Passat Wagon
I've just installed different injectors and have a fuel leak at the top of the 4th injector, where the hard line goes in. Fuel is coming out the top of the union where the hard line goes through. From this alone I assume it has to be the hard line/ injector interface not sealing properly when the nut is torqued up, otherwise how would the fuel get this high up the injector?

I have slackened, cleaned and re installed with IP end loosened but still leaks. I did find a bit if grit, wiped away and still leaks:(

Return hose lines are new for info. Will remove again when cooled down and have another look. Very annoying! Maybe the new injector sealing face at he top is scored?
 

buildingup

Well-known member
Joined
May 29, 2010
Location
Washington, Mi
TDI
None
For running regular diesel can I go to the parts sure and just buy a generic tube and cut to length or does this ned to be anything special? Whats recommended?
 
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