How to bleed air from fuel lines and pump?

Florida Blue

New member
Joined
Apr 15, 2007
Location
NC
TDI
2006 Jetta
Problem: I changed the fuel filter but forgot to fill the cannister with fuel. Car started, ran 15 seconds, stumbled, and died. I removed the cannister lid; it refilled when the engine ran, but I believe air got pumpted to into the round, silver metal fuel pump located on the driver's side of the valve cover. The car Will Not Start.

Request: Can someone please tell me how to bleed air out of the lines?

I am reluctant to begin disconnecting lines for fear of creating more air pockets ... until I know either which line(s) to disconnect and prime or where a bleeder screw on the fuel pump is located. [Note: my cannister does not have a bleeder valve.]

Please advise. I really need this car back in service. I know there has to be a simple fix.

Thanks in advance!

Model: 06 Jetta TDI, 20k miles.
 

Lightflyer1

Top Post Dawg
Joined
Sep 13, 2005
Location
Round Rock, Texas
TDI
2015 Beetle tdi dsg
You should be able to just cycle the key on and off a few times and all will be good. Turn the key to the run position and wait a few seconds. You might hear the pump whirr a little. Do this two or three times and then try and start.
 

Florida Blue

New member
Joined
Apr 15, 2007
Location
NC
TDI
2006 Jetta
As it so often happens, just when I'm ready to give up I have an idea ... and it works.

I noticed that the silver pump on the driver's side of the valve cover has two hex head (not Torx) screws. Near the lower one is a tiny raised triangular arrow, showing that this is a return line to the filter cannister. I traced the line back to the cannister, and it was the hose that is closest to the headlight. The very front hose. I removed it, inserted a plastic line into a pot of diesel on the floor. I also pushed a clear line onto the exposed male fitting in order to ensure a stream of diesel wouldn't squirt onto the alternator.

Turned the key, watched the clear hose from the return line, and saw fuel and air bubbles coming out. Decided that enough air may have been purged to allow a start, I removed the clear hoses and reconnected the black hose to its fitting.

Turned the key, cranked a bit, and it started.

I'll remember to fill the cannister with diesel next time I replace the filter. :)

Thank you, Lightflyer1, for your help. Maybe repeatedly turning the key on and off helped, maybe running out some air helped. I don't know. It starts. I'm happy. ! !
 

cujet

Veteran Member
Joined
Jun 5, 2005
Location
Florida, Hurricane central
TDI
2006 Jetta
My fuel pump does not run at all when cycling the key. The fuel pump in my 06 only runs when the engine is running.

This made troubleshooting my fuel pump failure (fuse issue) very difficult.

Chris
 

Lightflyer1

Top Post Dawg
Joined
Sep 13, 2005
Location
Round Rock, Texas
TDI
2015 Beetle tdi dsg
When I did mine, I just turned the key on for 30 seconds or so. Then off and repeat three times. There was a slight whirr noise at the start of each key on sequence. Started right up.
 
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