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I again recently repurchased a TDI only 8500 miles on it (2014 Jetta). This is my second tdi purchasing. First one when diesel emission hit (buy back). My 2013 was best car I ever owned so here I am again with a 2014 TDI

Does anyone know how to to prime fuel lines after a fuel filter change without vagcom on a 2014 TDI? I hear that air is bad if not primed.

I have obdeleven I used with my mk7 gti but I lack experience using it with my mk6 tdi.
 

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Greetings. I hope you went through official introductions - in the Intro Forum, otherwise Keith will be after you... :)

I am not that familiar with Mk6 & 7, so take this with a grain of salt . Maybe someone else will have a better answer for you.
I assume you can run the fuel pump without engaging the starter, as you can with most diesel engines. If I'm not mistaking, all late(r) TDIs have a fuel pump (starting with late MK4s).

The injection pumps are self-priming, but it helps to prime the lines... I assume you can fill the new filter with fresh diesel fuel, it cuts on the priming. You then could use a hand vacuum pump (MityVac) - with a long(er) clear tube to avoid getting diesel into your hand pump - to prime the fuel line. It shouldn't take much... I hope this helps.
 

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I read this post yesterday he isn't really asking important info as obdeleven isn't a true scanner. I'm sure he must have tried it on his 2014 Jetta TDI and it didn't work.
 

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Sorry to say that injection pumps are not self-priming. Running a CR HP pump without diesel will destroy it.
The method with the vacuum pump works with older diesels like an ALH, but not with CR diesels of CY 2014. Here priming must be performed with a diagnosis tester which supports basic settings and operating the pre-feed pump.
 

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audi1z - thanks for the info/correction. Running the HPFP dry will cause damage. Not sure this is such a case. I guess the question still is how exactly to prime the lines. Any specific recommendations - beyond operating the tester??

There have been reports on catastrophic failure of HPFP - very expensive occurrence, with plenty of speculations about the cause. Some examples on the potential cause: bad batch of pumps, lower lubrication properties for US diesel, lack of proper priming etc... So - many people are extremely concerned/careful about this topic. There are reports that for a simple fuel filter change VW trained technicians are cycling the key to activate the pre-feed pump, while others report that this step is skipped by many. BTW, I would appreciate if someone could confirm that cycling the key does energize the pre-fuel pump(s) on newer TDIs. I am not sure that's the case.
This being said, I don't believe the service manual talks about priming procedure for a fuel filter change. I found the info below - likely for a fully drained fuel system. Up to each individual to decide if such procedure is necessary/appropriate for a fuel filter change. One can make it as complicated as desired.

I hope someone else can offer better advice or point to a better resource.

Up to Justin to decide what works for him. Oh, and Justin - I would look into purchasing a VCDS (RossTech) if/when the finances allow it. It is definitely worth the investment when you own a TDI...

Bentely fuel system priming for CBEA engine
Bentely fuel priming
Diesel fuel system priming

Any time the diesel fuel system is opened or drained for repairs,prime the system before running the high pressure fuel pump.
Running the fuel pump dry causes damage.

-Make sure the fuel tank is filled.

-Connect Volkswagen scan tool or equivalent to OBD ll plug in driver footwell.

-With ignition switched ON, working at scan tool:
Select Engine Electronics in OBD.

Select 04-Basic Setting function.

Enter 35 with keypad. Confirm selection with Q

Press Activate.

-Allow electric fuel pumps to run for approx. 60 seconds

-Repeat procedure three times to ensure that high pressure fuel pump is filled with enough fuel.

-Start engine and run at idle speed to moderate speeds for a few minutes,then stop it. Check fuel system for leaks.

-Read out and clear DTC memory.

-Perform road test the is longer than 12 miles (20 km). Make sure accelerator is pressed down completely at least once. Recheck fuel system for leaks.

-If there is still air in fuel system, the engine may switch to limp home mode during road test. Stop engine, then read out and clear DTC memeory.

Repeat road test until fuel system is fully bled.
 

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Greetings. I hope you went through official introductions - in the Intro Forum, otherwise Keith will be after you... :)

I am not that familiar with Mk6 & 7, so take this with a grain of salt . Maybe someone else will have a better answer for you.
I assume you can run the fuel pump without engaging the starter, as you can with most diesel engines. If I'm not mistaking, all late(r) TDIs have a fuel pump (starting with late MK4s).

The injection pumps are self-priming, but it helps to prime the lines... I assume you can fill the new filter with fresh diesel fuel, it cuts on the priming. You then could use a hand vacuum pump (MityVac) - with a long(er) clear tube to avoid getting diesel into your hand pump - to prime the fuel line. It shouldn't take much... I hope this helps.
Priming the return line with a hand vacuum pump it should take all the air from the fuel line. It´s an ancient recipe.
 

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I too had a 2013 TDI. It was Passat SEL, and was the best car that I have owned. Put 100,000 trouble-free miles on it before VW offered me a deal I could not refuse. and after I found a new 2015 to replace it.

On priming the fuel pump.... If you hit the start button without pressing the brake pedal, that will run the tank pump for 3 seconds. Do that 3 or 4 time, and it will be primed. Do add as much clean fuel in the filter housing as it will hold before closing it up. So be sure to have about a quart of clean fuel before you start the filter replacement.
I did this every 20,000 miles on my 2013, and have done it twice on my 2015.
 

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I have a question about what I've just done to my 2007 Passat TDI. I replaced the fuel filter and seal (MANN brand) and filled the canister up to the top before replacing the cap. I was under the impression that my model would initiate the fuel pump on pressing the key to the on position so I wouldn't need to do a VCDS priming. The car started up just fine, it idled a little rough but evened out and it drove fine.
When I restarted the engine it took about 4-5 seconds of turning over before it will start. It's been like this for a week or so, and it even sometimes stalls when driving in traffic. I did some research and borrowed a VCDS setup, did the fuel priming steps as I've seen demonstrated on youtube etc. I can hear the little relay clicking on and off but I can't hear the fuel pump at all. I even lifted up the seat to listen directly on the cover of the fuel tank and I can't hear a thing, nor feel any vibrations.
I wonder if I have somehow done in my fuel pump? Is there a way in vcds to test the fuel pump without an electrical tester?

I'm sorry if i have posted this in the wrong place.
 

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First posts normally go in introductions else you could get a free fix and we never see you again!!!

Forum Rules and Guidelines

Even though this forum is good I can't select your post and move it to a new thread, that is a bad feature which I can do on other forms.

Any problems search TDI Wiki as that covers write ups and forum posts.
 

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Digging up an older thread but I figured out how to run the fuel pumps on a MK6 with OBDeleven. Find output tests under engine then pick selective. You can then search for pump which finds both the lift and aux pumps. Channel 35 gives me an error so you can't run both at the same time.
 

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A simple fuel filter change DOES NOT need VCDS or any other scantool.

Remove upper cover and remove old filter
Suck out fuel from canister
Insert new filter (w
ith new gasket)
Fill canister with fuel (I use Diesel Purge)
Wait until fuel is fully absorbed into filter
Top off to overflow
Replace upper cover

Car will start and run first try with no problems.
 
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