Fuel filter change: bleed or not bleed trapped air?

[bnud3]

Hi!

Car is Fabia BBY 1.4 16v.

I'd like to change fuel filter. The change itself seems quite straightforward. But I'm confused if I need to bleed the system (getting rid of trapped air) at the ventilation opening on the injector rail or not.

I've read a guide somewhere here in which it was not bled. But according to workshop manual, you have to bleed it: my problem is that some special adapter valve and a VAG remote control is needed to carry out the bleeding (which I do not have).

So can I simply omit this step? will the trapped air escape anyway?

Thanks!

[bnud3]

In the meanwhile I found these:

changing fuel filter, no bleeding done:

http://www.golfmkv.net/blog/archives/10#

Also found this one (VW Jetta fuel filter change procedure. You can observe the additional special adapters that are needed to bleed the fuel system):

http://www.keepandshare.com/doc/990557/fuel-sysyem-bleeding-pdf-december-29-2008-3-34-pm-121k?da=y

It says:

"Fuel System, Bleeding

Note:

If fuel supply system was opened, it must always be bled before

starting engine.

If fuel supply system is not bled, catalytic converter will be

damaged."

So is this a DIY job, or should I take to Skoda service?

[rum4mo]

Hum, I should be interested in this as my wife's Polo with a BBY is coming up for eight years old and 69,000 miles - I've thought about buying a filter many times but have been put off by the "with" or "without" pressure regulator description in ETOS. I've got VCDS and could probably get hold of connectors to get onto the fuel rail - so priming the system, if its needed should not be a big problem.

Either way, I'd reckon that the plastic fixings would need to be shown a lot of respect!

Edited 8 September, 2010 by rum4mo

[bnud3]

I already bought the filter (with integrated 3 bar pressure valve): 6q0201051b (original VW supplier, seems completely identical to Mann wk69).

Actually, the engine started to run very-very roughly - affecting all cylinders so I have a feeling that it might be caused by a clogged fuel filter. I already swapped the coolant temp sensor in the thermostat, but no improvement.

So I bought the filter, but now hesitating because of this bleeding procedure. No idea where I can get these valve connectors.

How risky is it to omit the bleeding, really? Should I expect that the air escapes through the injectors?

[bnud3]

So, I changed the fuel filter.

And I also bled the system! Sort of. What I did is that after I installed the new filter, I connected only the IN and RFL (return flow line) line but left the OUT line disconnected. Then I turned the ignition key into accessories 2 or 3 times, but did not crank, switching on the fuel pump for a few seconds several times. Thus the pump filled the empty filter with fuel (don't forget to put a catch can under the filter). Finally I connected the OUT line. I think with this procedure you can minimize the air blocks in the fuel line.

Now about my engine problem: unfortunetaly this did not solve it, it still runs very roughly so that I can not use the car. When idling the engine always stalls. I already changed the temp sensor, cleaned the throttle. What is left: fuel pump, spark plugs (I don't think it is the spark plugs though, because all cylinders seem to be affected), injectors? But suspect the fuel pump does not deliver the 3 bar pressure. Probably it is an easy change, but the pump itself is expensive. Can I somehow check if the pump is OK. Verify the pressure with VAGCOM? Any ideas?