TDI Fuel Pump Seals Failure?

rain_city_jim · May 19th, 2009, 12:43

Hey everyone -

This is my first post and since I could not find this tread, I am posting it.

What does everyone/anyone know about Fuel Pump Seal Issues (degredation) in hte VW Jetta TDIs?

I have a 2002 Jetta TDI. Just yesterday, it stopped running. The engine turns over, but does not start. I took it in to my mechanic, as it seemed that it was getting no fuel (clear fuel line was empty). This was confirmed. They re-primed the fuel lines and got the engine started. They ran the engine for a while and drove it. No problems. They stopped the car and then returned to start it a while later. No go. Fuel lines dry again.

It has been explained to me that the Fuel Pump Seals have failed and now the fuel system no longer has a constant vaccuum, which lets the fuel lines go dry. It was also explained to me that the VW TDI Fuel Pumps (or at least the ones for my year/model) cannot be refurbished and require complete replacement. This replacement is being quoted to me at about $2,300.

When I asked why/how this happened, I didn't get a very clear answer. I run BioDiesel in my car for 9-10 months of the year and a 50/50 mix (at most) in hte cold months to prevent gelling. I asked if either the Bio, the mixing, or just plain diesel (even low-sulfur) could have caused this. I did not get a clear or committed answer.

I have made a call for a second opinion, which lead me to believe that maybe the Fuel Pump could be refurbished with new seals.

I am not aware of any VW Recall on Fuel Pumps.

Sorry for the lengthy post, but has anyone else had this problem (anyone in hte Seattle area)? Does anyone have any good advice?

Thanks for hte help!!

2004STARWARSTDI · May 19th, 2009, 14:20

When you run Bio it swells the seals, the when you switch back to ULSD the seals shrink. Thus you have a leaking IP that will not pull the fuel. There are some rebuild kits for IP that include seals. Don't know about yours though. You have found out why you should stick to ULSD and it has been a costly experiment. Bio can not be found everywhere and you will have problems in the winter. Bio is not friendly to your fuel lines.

Also the IP might not be a problem. You could have a leaking fuel fiulter or a bad thermostatic T. To test if it is really the IP >remove fuel line at filter that goes to IP>insert the end that went to fuel filter into a small clean container of diesel>If IP draws diesel out of container & car runs then IP is good, and you have an air leak around fuel filter.

dogdots · May 19th, 2009, 14:47

My 02 had the same problem. Find the guru in your neck of the woods, a newly reconditioned one should be 1/2 that plus labor, and you might as well do the timing belt, rollers, and water pump while you are in there, still less than the original quote just to rebuild your pump.

paramedick · May 19th, 2009, 17:09

DFIS in Portland, OR can repair the pump. In most cases, between $500-800, dependent on what has to be replaced to return it to new conditon.

I dunno what a guru in your area will chage to swap it out. If I was doing the job, I would change the TB system unless it was new, and charge a bit more for the IP swap.

rain_city_jim · May 20th, 2009, 21:17

Thanks for the tips and advice everyone. I have a few options for shops in Seattle. I will mention the issues you all brought up.

Anyone else out there (running Bio) had this issue?

Thanks.

mannytranny · May 20th, 2009, 21:43

Yup. In my case, it was a $9 o ring.

http://forums.tdiclub.com/showthread.php?t=246142

Lots of learning, but I got it all back together myself.

I ran B80, then switched to D2 and the leak showed up 5 miles later. My o ring was visibly cracked.

So much for that line 'Most vehicles made after 1998 have Viton rubber used in the fuel system and are thus biodiesel ready.'

terrydtdi · May 21st, 2009, 01:54

Wait before you do that I had the same problem with my car a few mounths back .
If you haven't put a new fuel filter in recently , change it out that took care of my problem .
I thought I needed to do the same thing with the pump , try this and go with ULSD for a while and see if you don't have any more problems .
I quit running bio all together and haven't had any problems since.

terrydtdi · May 21st, 2009, 02:02

Here is the thread from when I had problems when I ran Bio a while back see if this matches yours. Since I have quit running bio I haven't had ANY problems.

http://forums.tdiclub.com/showthread.php?t=224300

BioDiesel · May 21st, 2009, 04:10

I had the same problem when I switched from LSD to WVO in 2003.
Had to replace two fip seals. Been fine since because I scrupulously avoided LSD. Went to grocery stores for 1/2 gallons of Wesson.

MAny more fips leaked when ULSD was introduced in 2007.
LSD and B100 swell seals, WVO and ULSD don't, and the seals shrink by 1/3.

If it's your top cover seal, you can do it yourself easily.
Head seals are difficult, but there are HOW-TO threads here.
I did mine, a friend was not so lucky.
Sometimes the main shaft seal goes necessitating fip removal.
FWIR many are repaired w/o removing the fip.

Viton seals are available now iirc. Ask in the AltFuel section. DieselGeek maybe?
If you don't get Viton, and still want to run bd, just stick within a narrow range of blended fuels. like B20 to B50.

You could possibly reswell your seals. If you can force B100 through it.
If it's the fip thats leaking, you could hook it to a quart of B100 and pull it through the fip with a MightyVac and let the seals soak and swell a couple days.

BioDiesel · May 21st, 2009, 04:35

"So much for that line 'Most vehicles made after 1998 have Viton rubber used in the fuel system and are thus biodiesel ready.'"

Hi Manny,
I know this is meant to be a joke, but it is misleading.
The seals ARE bd ready.

If you take new seals, and run them always on B100, you'll never have a problem. The seals won't degrade. I've got seals that have been sitting in jars of SVO and B100 in my garage since 2003. They didn't shrink. You can do the same on LSD, WVO or ULSD.

The problem arises when SWITCHING between high aromatics ( LSD and B100 ) and low aromatics ( ULSD and WVO ).

DanG144 · May 21st, 2009, 10:09

Can anyone point me to some guidance on how to replace the main shaft seal on the A4 injection pump? It looks as if I will need to do the QA and head seals as well.

Searching has turned up huge amounts of stuff, but not what I need.

The vehicle is one that starts on ULSD then is switched to WVO. Since both are low aromatics, do I need viton seals?

Does anyone have a source for viton seals for the IP shaft and QA? I know DieselGeek sells viton IP head gaskets.

fruitcakesa · May 21st, 2009, 16:57

My 02 had been running BD blends from B20-B100 for 70k miles and one day I parked it and itwas dead the next morning and fuel was pouring out the IP head seal.
I bought the DG viton seals [I bought a spare in case of problems] and repair studs.
Nervously following the online instruction I was able to do the fix with no "uh oh's'".
Cost 20 bucks and 3 hours of work [I went very slowly]