#1 injector blowing bubbles?

[chad1966]

Why is my #1 injector blowing diesel bubbles? I see that the small hose that connects each injector is wet. Could it be seeping out in settling there and then just boiling? Thanks in advance.

https://www.dropbox.com/s/cogvhzf0h7...%2013%20PM.mov

[anders]

The link you posted doesn't work, where are the bubbles? Between injector and cylinder head? If so the heat shields are not properly sealed.

[chad1966]

Fixed the link and yes between the injector and head.

[ngoma]

Originally Posted by chad1966

I see that the small hose that connects each injector is wet.

If the injector return lines are leaking you need to fix that first. You DO NOT want fuel to drip down onto the rubber coolant lines below. Take care to not scratch or otherwise damage the small barbs on the injectors.

[745 TurboGreasel]

First the fix line.
If someone had the injectors apart, it isn't too hard to crack them by overtightening the case laves together .

[RedArrow]

Originally Posted by anders

The link you posted doesn't work, where are the bubbles? Between injector and cylinder head? If so the heat shields are not properly sealed.

Yesterday I drove a few hrs 180 highway miles mostly at 75-80mph; after a quick check-up at a gas station I noticed very very tiny bubbles at injector 1 (front). No leak-downs, just a few bubbles in the gap where injector sits in head. Only there. Rest of my injectors have no leaks, no bubbles.
All the hard lines are completely dry, always been, also, all the return lines are completely dry, always been.

I dont have starting or running issues at all, all is fine, but what`s suggested as next step to quickly address this problem? Why did it show up?
Get the inj out? or only tighten it? Is it suggested to replace all shields btw? I`m planning on new fuel return lines between injectors anyway. What`s the torque specs on the hard lines? They surely hate being overtight.

Thanks in advance.

[ngoma]

Clean that area really well, then watch it. If there is some liquid down in there from whatever, it will bubble (boil?) when hot, because, it's really hot there. IOW, bubbles there do not always indicate pressure leaking out.

I listed the hardline torque value somewhere here in the past, bet you can find it faster than I on my slow connection.

[RedArrow]

Originally Posted by ngoma

Clean that area really well, then watch it. If there is some liquid down in there from whatever...bubbles there do not always indicate pressure leaking out.

Thanks NGoma, I noticed the bubbles thanks to some very very small stain-spots (engine oil?) on nearby dry parts that were a bit dusty too, so they showed a couple fresh `dots`on them.
When it comes to leaks, I`m OCD+paranoid, so I immediately searched for a while then tracked down those bubbles being at the base of first injector.
It did look like there was `boiling` going on. Nothing crazy, just 2-3 small bubbles visible. I should have taken a sample onto a paper towel but I was on a long trip and there were no wet injector lines involved (nor a hard fuel line being loose). By the time I got home...I forgot to re-check.

You are right, it can be some liquid `boiling`. Good point -- because recently I had to realize that my engine oil cap seal is not perfectly sealing. There`s no other liquids there, like coolant etc, car hasn`t been washed etc. I need to check another connection though, as i do have occassional atf dripping below the PS which could* `travel/fly` to inj when vibration&speed combine with winds. Also, minimal amount of motor oil finds its way down on the passenger side of the block; coming from the cap on top. I guess.

Originally Posted by ngoma

I listed the hardline torque value somewhere here in the past

I found what you wrote,thx.
You will want to perform the troubleshooting routine at idle where you loosen one-by-one the injector line nuts at the injectors and see if any do not lower or worsen the idle. This to find if there is a particular injector, line, valve, distribution valve, cylinder, etc. that is the problem. Do not over-tighten the injector line nuts when closing them up. 25Nm / 18ft-lbs.


What`s the best injector removal tool?One day it`ll be needed anyways so I searched this:
http://www.ebay.com/itm/27mm-VW-Audi...196748&vxp=mtr

[745 TurboGreasel]

My 27MM socket fits em fine, but some don't.
It's 55 ft/lb for the case halves.
Dry with brake clean, then dust with flour, makes the leak easier to pinpoint.

[RedArrow]

Area got cleaned and tested at (high) idle. I saw no bubbles forming (no wetness) so I suspect a few drops of engine oil somehow landed in there. Thank you for your quick replies. Heat shield is fine I think.

(I still plan getting new return lines installed, although they are OK&dry. No issues there. A few showing age, not seated all the way down and 4 of them (got) pretty short. )

I`ve seen d24ts with transparent lines installed, which may not be a dead idea when/if trouble comes. (?)