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Engine Specific Info and Questions => TDI Engine -General Info => Topic started by: Smoker on July 11, 2014, 11:30:57 am

Title: losing compression around #4 injector
Post by: Smoker on July 11, 2014, 11:30:57 am
I cleaned the seat area, replaced the little washer, and torqued the bolt to spec.  I'm still losing compression around the injector. (I can see it bubbling when I spray it down with a little PB blaster)... what am I missing?
Title: Re: losing compression around #4 injector
Post by: libbydiesel on July 11, 2014, 11:52:33 am
You are misconstruing the results of your 'test'.  If you spray solvent around an injector, then when the area heats up, the solvent will bubble out as it evaporates.  The bubbling will happen regardless of whether or not you have a compression leak.  The same thing happens when diesel leaks down around the injector.
Title: Re: losing compression around #4 injector
Post by: Smoker on July 11, 2014, 12:38:20 pm
Interesting.  It wasn't really a 'test'... the head happened to be pretty wet around all the injectors, as I had sprayed it down when I swapped them out.  I just happened to notice it blowing out around the #4 injector but not the others.  When I sprayed more, it continued to bubble around #4 but none of the others.
Title: Re: losing compression around #4 injector
Post by: 745 turbogreasel on July 11, 2014, 01:28:53 pm
Sounds like a fuel leak  needs fixed first.  Was the injector apart or  untested?
Title: Re: losing compression around #4 injector
Post by: libbydiesel on July 12, 2014, 01:11:23 am
Is it bubling out or blowing out.  You've said both and yet, those two symptoms are very different.  If it is forming bubbles that are then popping, I would not have any concern.  If it is spraying the solvent back out without forming bubbles, then I would be concerned.
Title: Re: losing compression around #4 injector
Post by: Smoker on July 12, 2014, 11:18:55 am
Is it bubling out or blowing out. 

I'll have to try it again and get back to you on that.  When I saw it happening, it gave me the idea that it was blowing out, not boiling, but the more I think about it, the less sure I am...

The motor is actually out of the car now... in the meantime I'm planning on having the injectors pop tested, as I don't know anything about the history of this motor, and I need it to be right.