[Jim W]

Ok guys I am use to a Cummins diesel in my 08 Mega Cab. We pull a 5er with it and I have learn quite a few things I need to do to maintain the Cummins.
So on a Jetta TDI or another VW diesel, is there a water-in-fuel sensor and does an idiot light come on in the car? Could not find one mentioned in the O and M Guide.
Do you guys carry a spare fuel filter in case of plugging ?
On my Mega Cab I have two filters the factory 5 micron and my aftermarket 2 micron fuel filter. So I carry two filters to change out.
Jim W.

 

[DAVE PARKER]

Jim
My 2010 Jetta TDI wagon does not have a water sensor. I do not believe that the 2011 Jetta TDI has one either. So far after 28k miles (and two winters) I have not had a water issue.

I have replaced the fuel filter at the 20k factory service interval.

cheers
dave parker

 

[TDILow3]

My 2011 JSW TDI has just a simple filter assembly with no water drain off port nor a filter minder for water.

I share your skepticism regarding the staunch difference between a light duty truck diesel fuel system (stacked systems of filters, water separators, water drains, filter minders...). However, the data suggests that the current TDI design does not require the aforementioned components. The only explanation I can offer is the TDI fuel heater recirculation assembly inside the filter housing, which uses the heated fuel returning from the common rail to pre-heat the incoming fuel. I speculate that this pre-heat increases the fuels ability to prevent the water from precipitating out of solution and in a sense dries the fuel by increasing the absorption abilities.

With the elaborate system of stacked electric fuel pumps, a high pressure fuel pump, sensors...I truly believe that all of the data necessary to create a 'clogged filter' alert on the MFID is already present and it would just take a software update to make it happen.

I don't carry a spare fuel filter with me, but I do have one on the shelf at the house, along with a VCDS equipped netbook to perform the fuel filter purge cycle to get the air out of the system and prevent the high pressure fuel pump from ingesting any air.

 

[Jim W]

Thanks for the replys. But I do have another question?
What is; a VCDS equipped netbook to perform the fuel filter purge cycle. The fuel system does not self purge?
Jim W.

 

[chittychittybangbang]

Yes, see the 09+ TDI fuel filter change article for the screenshots. The fuel system does "self purge" through normal running but the manual says to run the filter to fill it and prime the system. The system will not do that otherwise. I don't know why, but older models primed the fuel tank fuel pump when you turned the key to ON. The 09+ only prime the fuel tank fuel pump when you turn to START or are running.