2005 Jetta massive fuel leak

bigjake

Veteran Member
Joined
May 7, 2015
Location
Charlottesville, VA
TDI
2005 Jetta MKIV, 1.9 BEW with 09A
Hey guys,

so earlier today, my girlfriend and I were traveling to a nearby city to run some errands. As we started up Afton Mountain, I noticed my car was smoking. I needed to find a place to pull off, but Afton Mountain is a very dangerous stretch of highway with no shoulder. So I had to keep driving a few miles uphill until we got to a huge pull off. I turned off the car as soon as I pulled off and there was heavy smoke pouring out from under the hood at that point. It didn't smell like it was burning and I didn't feel abnormal amounts of heat, so I popped the hood. I noticed there had been a massive diesel leak on the right side of the engine. I traced the fuel lines from the fuel filter around the motor and everything looked good up until I got to the right side. AAA eventually took me and the car home, but I have yet to really look at it.

I've been poking around online and it looks like either a fuel line ruptured or the tandem pump catastrophically failed. The leak was so bad (it continued to leak fuel onto the rollback over an hour after it was shut off) that I feel like it was probably the tandem pump. But how was it that I was able to casually continue driving up hill with no loss of power until I shut the car off? Perhaps maybe it was a fuel line after all? :confused:
 

Tdijarhead

Top Post Dawg
Joined
Nov 10, 2013
Location
Lawrenceville PA
TDI
2003 TDI Jetta Daughters Car, 2001 TDI Beetle, Wife’s car, 2005 Golf TDI Mine, all 5 spds
Would that be rt 250 right after you get off of I 64?

You'll have to take a look , tandem pumps do spring leaks occasionally but then so do hoses.
Either way it shouldn't be to bad to replace. Idparts has the tandem pump and hoses also.
If it is a hose and you source locally, make sure it's rated for diesel or you'll be doing it again shortly.
 

jptbay

Veteran Member
Joined
Aug 9, 2007
Location
Thunder Bay
TDI
2003 Beetle, 2006 Jetta Wagon
Just had similar leak on our Bew wagon. Was a pin hole in the short fuel line going to the tandem pump from the metal fuel line on the valve cover.

New hoses are pricey as they are only available to buy in a package with the metal fuel lines.

I had a spare ALH fuel line and was able to cut out a similar bend in the molded line, and use that.
 

Dimitri16V

Top Post Dawg
Joined
Jan 30, 2005
Location
DE
TDI
01 Golf, 04 Golf
Those hose that connect to the tandem pump leak over time

I replaced mine with polyurethane hoses
 

TDIGAZ

Veteran Member
Joined
Jan 15, 2008
Location
Eastern Ontario, Canada
TDI
Current: 2003 Jetta GLS Grey 5 spd. Previous: 2003 Jetta GLS Silver 5 spd (lost in a collision)
Also check your thermostatic tee on the fuel filter, especially if you've done a fuel filter change lately.
A friend of mine had a hairline crack in the tee (which was not easy to see) and this caused a big fuel leak.
 

bigjake

Veteran Member
Joined
May 7, 2015
Location
Charlottesville, VA
TDI
2005 Jetta MKIV, 1.9 BEW with 09A
Would that be rt 250 right after you get off of I 64?

You'll have to take a look , tandem pumps do spring leaks occasionally but then so do hoses.
Either way it shouldn't be to bad to replace. Idparts has the tandem pump and hoses also.
If it is a hose and you source locally, make sure it's rated for diesel or you'll be doing it again shortly.
Yup! Sure is! I got caught on the big over look on 250 right before the Blue Ridge Parkway entrance. We were headed to Waynesboro.

I'm in the process of pulling it apart now. There was fuel sprayed on the top of the engine and I see no leaks in the tops of the fuel lines. The more I pull it apart, the more I'm suspecting it's the pump. Fingers crossed it's the hoses. I'll keep yall posted.
 
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Tdijarhead

Top Post Dawg
Joined
Nov 10, 2013
Location
Lawrenceville PA
TDI
2003 TDI Jetta Daughters Car, 2001 TDI Beetle, Wife’s car, 2005 Golf TDI Mine, all 5 spds
Awesome view from the top heading down.

Did you find what was leaking yet?
 

bigjake

Veteran Member
Joined
May 7, 2015
Location
Charlottesville, VA
TDI
2005 Jetta MKIV, 1.9 BEW with 09A
Awesome view from the top heading down.

Did you find what was leaking yet?
I began tearing it down on Saturday but my work got cut short and I haven't been able to get back to it since. Most of that work consisted of getting crap out of the way to create space. I won't be able to continue work until tomorrow. My stopping point was, I was able to pull the pump's top hose off which was fine. That leaves either the bottom hose or the pump as the failed part. I haven't pulled the bottom hose yet but I felt around it and felt no major holes or gashes. The more I dig, the more I'm becoming positive the pump is what failed.

Is it common for the gaskets to suddenly fail and cause such a huge leak or does it sound like the whole pump failed? I'm praying that the gasket is what failed. Those pumps are extremely expensive and I don't know that I can afford one anytime soon.
 
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bigjake

Veteran Member
Joined
May 7, 2015
Location
Charlottesville, VA
TDI
2005 Jetta MKIV, 1.9 BEW with 09A
Ok, so I've been working further on it. The vacuum hose on the back of the pump was extremely loose. Someone had messed with it before. There wasn't a factory clamp on it. I could twist the hose almost 180 degrees (and probably could've pulled it off) with my fingers before I even started loosening the clamp. Thought this isn't good, this hose shouldn't have been the cause of the leak though, right?
 

bigjake

Veteran Member
Joined
May 7, 2015
Location
Charlottesville, VA
TDI
2005 Jetta MKIV, 1.9 BEW with 09A
Awesome view from the top heading down.

Did you find what was leaking yet?
Ok, I finally got the pump off. All fuel lines were totally fine and leak free. I started messing with the pump. I pressure tested it by mouth (I know that's not a lot but I don't have anything else to do it with) and everything seems solid and sound. I know now that even though that vacuum hose was loose, there's no way it was the culprit. I checked around the back of the engine to see if there was any remaining leaked diesel indicating the injector pump or something else back there leaked, but everything looked dry/clean. I double checked the fuel filter and the lines/rails going to and from the tandem pump and everything looks good. There is a lot of oily gunk on the block around where the tandem pump sits. There is remaining fuel directly above it on top of the engine and fuel directly below it on the the top of the transmission. Based on the area of the spill and the condition of the pump, I believe the evidence is mounting, that this is all because of a failed tandem pump gasket. It looks worn and there are some areas on it with some small weird blue stuff. I have a gasket coming to me in the mail at this time.

I honestly can't think of anything else that could have failed based on my findings. What's bugging me though, is I've done a ton of digging in the tdiclub archives and I can't find one case where someone's tandem pump gasket worked all fine and dandy, then suddenly and catastrophically failed, causing a fuel dump in the engine compartment. Fuel was even was sprayed on the underside of the hood. I'm sure a failed gasket being the sole offender is not out of the realm of possibility but I feel like I'm missing something here. Can you guys think of anything else? :confused:
 

Tdijarhead

Top Post Dawg
Joined
Nov 10, 2013
Location
Lawrenceville PA
TDI
2003 TDI Jetta Daughters Car, 2001 TDI Beetle, Wife’s car, 2005 Golf TDI Mine, all 5 spds
As long as you've got one coming by all means replace it and see if that solves your problem. I just went out and took a look at mine, the one hose on the rear still has a factory clamp on it, but seems to be slightly loose. Maybe even weeping a bit, it's hard to tell. My TP has so far not given me any problems so I haven't had to play with it.

The blue stuff is probably RTV gasket sealer, someone probably had your pump off before so there's no telling what was done to it. Maybe they broke the old gasket and put a healthy dose of RTV on it and it held, till it didn't.
 

bigjake

Veteran Member
Joined
May 7, 2015
Location
Charlottesville, VA
TDI
2005 Jetta MKIV, 1.9 BEW with 09A
As long as you've got one coming by all means replace it and see if that solves your problem. I just went out and took a look at mine, the one hose on the rear still has a factory clamp on it, but seems to be slightly loose. Maybe even weeping a bit, it's hard to tell. My TP has so far not given me any problems so I haven't had to play with it.

The blue stuff is probably RTV gasket sealer, someone probably had your pump off before so there's no telling what was done to it. Maybe they broke the old gasket and put a healthy dose of RTV on it and it held, till it didn't.

Possibly, I don't see any cracks or breaks on the gasket. The stuff is sitting in vary small clumps randomly arranged around the middle of it. I saw it both on the block and the gasket. I hope it's not any kind of corrosion. I'll let you know what happens after I put the new gasket on.
 

Tdijarhead

Top Post Dawg
Joined
Nov 10, 2013
Location
Lawrenceville PA
TDI
2003 TDI Jetta Daughters Car, 2001 TDI Beetle, Wife’s car, 2005 Golf TDI Mine, all 5 spds
Possibly, I don't see any cracks or breaks on the gasket. The stuff is sitting in vary small clumps randomly arranged around the middle of it. I saw it both on the block and the gasket. I hope it's not any kind of corrosion. I'll let you know what happens after I put the new gasket on.

Make sure you clean all that old stuff off of the block and the pump.
 

where2

Veteran Member
Joined
Oct 29, 1999
Location
North Palm Beach, FL, USA
TDI
One '13 JSW_TDI & One '04 Variant_TDI
That squirting tandem pump is a LUK with one yellow dot on top, about half way between the upper fuel hose and the rear vacuum hose isn't it?

Vacuum hose off the back going to the brake booster is a common hose requiring replacement. When I asked for a clamp when I was replacing my brake booster hose, I got a screw clamp tossed in the box. I was really expecting something resembling a fuel injection hose clamp, they don't chew up the hoses.
 
Joined
Nov 17, 2014
Location
Ventura, Ca.
TDI
2004 PD Wagon, Tiptronic
Question: are you sure it was diesel leaking and not coolant?

Lots of 'smoke' and a continued leak long after shutting down kind of hint at it being coolant to me. Both fluids are stinky and slimy so it's not impossible to mistake one for the other.

There is a small coolant line that runs beneath the tandem pump. Those pumps tend to weep diesel over time and the fuel drips right onto the coolant line. The line rots and swells and maybe pops spraying coolant all over.

Good luck,
Brendan
 

bigjake

Veteran Member
Joined
May 7, 2015
Location
Charlottesville, VA
TDI
2005 Jetta MKIV, 1.9 BEW with 09A
That squirting tandem pump is a LUK with one yellow dot on top, about half way between the upper fuel hose and the rear vacuum hose isn't it?

Vacuum hose off the back going to the brake booster is a common hose requiring replacement. When I asked for a clamp when I was replacing my brake booster hose, I got a screw clamp tossed in the box. I was really expecting something resembling a fuel injection hose clamp, they don't chew up the hoses.
The pump is definitely a LUK but I haven't checked for any yellow dots yet. I'm guessing you had a similar experience?
 

bigjake

Veteran Member
Joined
May 7, 2015
Location
Charlottesville, VA
TDI
2005 Jetta MKIV, 1.9 BEW with 09A
Question: are you sure it was diesel leaking and not coolant?

Lots of 'smoke' and a continued leak long after shutting down kind of hint at it being coolant to me. Both fluids are stinky and slimy so it's not impossible to mistake one for the other.

There is a small coolant line that runs beneath the tandem pump. Those pumps tend to weep diesel over time and the fuel drips right onto the coolant line. The line rots and swells and maybe pops spraying coolant all over.

Good luck,
Brendan
I'm absolutely 100 percent sure it was diesel. My car smelled profusely like diesel when I opened the hood, the color of the liquid was a blueish tint, not red, my temperature gauge never changed through the whole ordeal and the car refused to start after all the leaking stopped. I'll check the hoses underneath the pump to check their condition though. Thanks for pointing that out.
 

JB05

Top Post Dawg
Joined
Oct 20, 2005
Location
Il.USA
TDI
Golf,2005,anthracite blue
I had a recall on the tandem pump for my Golf, but forgot why. There is now a worm gear hose clamp in place of the factory crimp clamp for the vacuum hose.
 

bigjake

Veteran Member
Joined
May 7, 2015
Location
Charlottesville, VA
TDI
2005 Jetta MKIV, 1.9 BEW with 09A
This should have been the first thing done, but I didn't see that it was. Heck, just cycling the key to on should pressurize the system enough.
Cycle the key? Yeah, I don't think it's a smart idea to run my injector pump dry and risk killing that or my battery.
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
You have a low pressure pump in the tank. When you cycle the key to on, the pump runs and fuel flows from the pump, through the filter, to the tandem pump, then back to the tank with a restrictor in the tandem pump to maintain pressure in the distribution pipe.

The pump will only run for a few seconds so there is zero chance of causing any troubles.

With your comment about running the injector pump dry with a key cycle, I am guessing that you don't fully understand the fuel system on your car.
 

Mavrick

Veteran Member
Joined
Feb 16, 2012
Location
Ontario
TDI
2003 VW Jetta TDI
You could keep replacing good parts if you'd like... but I would prime the fuel system and start the car... see what leaks. Don't worry about running the pump dry, it will be fine.
 

where2

Veteran Member
Joined
Oct 29, 1999
Location
North Palm Beach, FL, USA
TDI
One '13 JSW_TDI & One '04 Variant_TDI
I had a recall on the tandem pump for my Golf, but forgot why.
Reminder why: NHTSA Safety recall VY, which is apparently closed (Based on 2015 TDI Forum comments from users trying to get their tandem pump covered). When I had my VIN run by a dealer I trust prior to buying my own replacement pump and swapping it myself (two weeks ago), I had no open recalls. My VIN clearly falls in the middle of the first VIN series listed in the recall, and my LUK pump clearly only had one yellow dot on it.

The recall notice is a fun read:
http://www-odi.nhtsa.dot.gov/acms/cs/jaxrs/download/doc/ACM4845766/RCRIT-04V586-7306.PDF
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
Is it a 2005 or a 2005.5? If it's a 2005.5, it most likely is NOT the tandem pump. If it's a 2005, it most likely IS the tandem pump.
 

bigjake

Veteran Member
Joined
May 7, 2015
Location
Charlottesville, VA
TDI
2005 Jetta MKIV, 1.9 BEW with 09A
You have a low pressure pump in the tank. When you cycle the key to on, the pump runs and fuel flows from the pump, through the filter, to the tandem pump, then back to the tank with a restrictor in the tandem pump to maintain pressure in the distribution pipe.

The pump will only run for a few seconds so there is zero chance of causing any troubles.

With your comment about running the injector pump dry with a key cycle, I am guessing that you don't fully understand the fuel system on your car.
I fully understand how my fuel system works. I actually found and read this file before I ever posted anything on here: http://www.myarchive.us/richc/VW_TDI_with_PumpeDuse.pdf Though I learned about my fuel system, I didn't find the answers I was looking for to troubleshoot the tandem pump. That's why I started this thread. Btw, You actually forgot to mention that when the fuel gets sent back, it gets measured by a fuel temperature sensor and runs through a fuel cooler located in the filter. Now, what I didn't fully understand is that it's apparently ok to run the injector pump, while dry, for moderate amounts of time.
 

bigjake

Veteran Member
Joined
May 7, 2015
Location
Charlottesville, VA
TDI
2005 Jetta MKIV, 1.9 BEW with 09A
Ok guys, the problem has been solved. What caused the sudden huge leak was the short upper fuel hose that goes into the top of tandem pump. It had a pressure sensitive leak. It looked deceivingly fine when I pulled it and when I conducted my own pressure test, it wasn't powerful enough to expose the leak. When I put everything back together after changing the tandem pump gasket, I discovered it when trying to start the car. I also discovered at that time that the tandem pump did in fact have a trickle leak to it. It was leaking between the outer black plate and the rest of the pump. I called the dealer about the recall but my car had already been serviced for it back in 2005 and my vin was therefore kicked out of the recall pool. I went ahead and replaced all the rubber fuel hoses under the hood and replaced the pump. Everything has been put back together and there are now no leaks. Thanks for all your help.

Case closed.
 
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whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
I fully understand how my fuel system works. I actually found and read this file before I ever posted anything on here: http://www.myarchive.us/richc/VW_TDI_with_PumpeDuse.pdf Though I learned about my fuel system, I didn't find the answers I was looking for to troubleshoot the tandem pump. That's why I started this thread. Btw, You actually forgot to mention that when the fuel gets sent back, it gets measured by a fuel temperature sensor and runs through a fuel cooler located in the filter. Now, what I didn't fully understand is that it's apparently ok to run the injector pump, while dry, for moderate amounts of time.
Nope. You still don't fully understand the system on your car.

One) There are four injector pumps on your car. They are cam actuated and one is located on each cylinder. The pump in the tank is NOT your injector pump.

2) There is no fuel cooler located on the fuel filter. There is a thermo-control fitting that will allow fuel returning from the head into the filter or bypass it, depending on temperature.

III) The pump in the tank is the only pump that runs in KOEO. The tandem pump and the four injectors are only moving in KOER.
 
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