Updated: Fuel Level Sending unit repair/replace 2002 ALH NB

[Rickstah]

Hi, all, ever since I got my Bug back from the dealership last fall I have been chasing an issue where sometimes it starts fine when cold and then if I've driven awhile it won't start back up for several tries, possibly even several minutes. Here recently I started noticed that is was possibly starting easier when I had it level or parked slightly downhill but didn't think much until last week when it just gave up the ghost one day immediately after I had just filled it up station has a non-level slab and I was facing uphill. Cranked for five minutes no joy. I finally thought why not and backed it down to a level spot and a few minutes later when I tried it started. I made it home and just parked it, and am just now replacing it. It was almost full, lol, so dealing with that...BUT...I need some confirmation on which line goes where, because I SWEAR when I took those lines off the blue line was on the tip that was closer to the metal frame it went under. I took the picture after I got the parts removed but you can still see the blue line was underneath and shorter...dangit, although I can't swear to it, they were both moving about while the process was happening...but I have seen two Youtube videos and the blue one was always the longer length of line going onto the tip closest to the inside edge of the pump.

Questions
1) would the car even run if these lines were reversed by the dealership?? Going insane, here, thanks, lol.
2) Do I need to depress the clip on bottom before the lines clip back down on the tip? Acting like they don't want to go down. NOTE: remove the white caps first, lol, crisis over for THIS question

 

[Rickstah]

OK, to make a long story short I was sent a unit with actual fuel pump in the assembly, not just a sending unit assembly, and it is the longer narrower plug type so I am trying to figure out what to do...would the sending unit on the one I was sent work if refitted to this old sending unit which was in a replacement tank they swapped into my Bug? My former sending unit was pretty spot on, I miss it, lol.

 

[csstevej]

Unless you modified your NB to have a fuel pump ……that year NB don’t have a fuel pump , it’s just a fuel sending unit .
The 04’s and later came with a fuel pump as part of the fuel sending unit , hence the 4 pins in the connector , the regular sending unit has two pins for the level indication.

 

[J_dude]

Ok this has been a little hard to follow, but looks like your old unit is the stock one for an ALH (no pump, just fuel level sender), the new one is for a BEW (has a lift pump). That is an upgrade, but I’m not sure if it will let fuel through if you don’t get the pump wired in though.

I’m not sure I understand, did the dealer install the new sending unit/pump and tank? And it was after they did that the starting issue began?

 

[csstevej]

You can modify your car to have the pump to work , just need wire , fuse and a relay….takes about 3-4 hours.
Just did this to one of my beetles , plan on doing this to our others.

 

[Rickstah]

Ok this has been a little hard to follow, but looks like your old unit is the stock one for an ALH (no pump, just fuel level sender), the new one is for a BEW (has a lift pump). That is an upgrade, but I’m not sure if it will let fuel through if you don’t get the pump wired in though.

I’m not sure I understand, did the dealer install the new sending unit/pump and tank? And it was after they did that the starting issue began?

Well, disappointing but enlightening. The moment you mentioned it I realized what i had done, I was reading the manual from the gasoline engine section, not the diesel section, which explains why I posted all the gasoline fuel pump pics, lol. Embarrassing but I understand now, only eBay guy was so sure it was the correct "fuel pump" for my model TDI, even guaranteed it. I blame myself for misplacing that memory. I guess while I have it out I should try to do the sending unit fix to get back the almost quarter tank of delta on the fuel gauge from this sending unit. Thanks to all for clearing me up. I guess my problem still exists, the just deciding to stop firing up. This was a long weekend, lol. I am going to delete a lot of this crap I put up.

 

[Rickstah]

Before I delete all this, since this is just a sending unit does the placement of the blue versus black fuel lines on the sending unit still apply? Because this who problem started when they replaced the tank...if the blue and black lines were reversed would it still run and would it lead to fuel starvation...because I lost a lot of boost after that. I am afraid to even formulate questions now, lol.

 

[Rickstah]

You can modify your car to have the pump to work , just need wire , fuse and a relay….takes about 3-4 hours.
Just did this to one of my beetles , plan on doing this to our others.

Interested, lol...possibly because now I have to take that pump out and decide whether to return it or not, lol.

 

[wonneber]

Return the used pump?
Good luck with that.
The "modify" option might be a better choice.
An electric pump should make fuel filter changes easier.

 

[J_dude]

Interested, lol...possibly because now I have to take that pump out and decide whether to return it or not, lol.

Yeah if it’s the pump for a BEW, that’s a common upgrade, just have to wire it in.

 

[J_dude]

And to help answer the original question: the Blue hose is the Return line, and from all the pictures it looks like it goes to the nipple that is closest to the electrical plug. If that last pic is the one in your tank right now I think you have it right.

 

[BobnOH]

Twer me, I'd just replace the fuel pick-up unit. Also, I doubt that fuel pick-up was causing the issue. More likely something in the engine bay has a small "leak".

 

[Rickstah]

And to help answer the original question: the Blue hose is the Return line, and from all the pictures it looks like it goes to the nipple that is closest to the electrical plug. If that last pic is the one in your tank right now I think you have it right.

Thanks, Dude. I think the blue line was flipped with the black one from that picture on the original. Would it have still run but with lots of issues, etc?

 

[Rickstah]

Return the used pump?
Good luck with that.
The "modify" option might be a better choice.
An electric pump should make fuel filter changes easier.

Currently looking for the procedure to wire it up as mentioned, thankfully have never had an issue replacing the fuel filter if you are talking about hard starting. Used to use a mighty vac to pull the fuel in, last several years have just filled the filter with Diesel purge and it has never failed to start.

 

[Rickstah]

Ok this has been a little hard to follow, but looks like your old unit is the stock one for an ALH (no pump, just fuel level sender), the new one is for a BEW (has a lift pump). That is an upgrade, but I’m not sure if it will let fuel through if you don’t get the pump wired in though.

I’m not sure I understand, did the dealer install the new sending unit/pump and tank? And it was after they did that the starting issue began?

Dude, redoing this thread to make more sense but my car was hit and they replaced the tank and it looks like they used the old sending unit because mine pre-wreck worked great and the lousy tape job on the plug cord tells me something not sure what. The young guy working on it at the dealership really messed things up other than the rear axle, which seems ok. Oh and he didn't seal back the tube from the fuel cap to the tank because if I try to top it off it starts leaking out onto the ground under the tube side of the tank. Cant make this up, lol.

 

[Rickstah]

So it is still sitting. If I could take the new sending unit off the gasser pump and put it on as the new sending unit on the old assembly would it work the same? I will just have to wait to see if it starts to find out if the lousy running was due to the swapped fuel lines or if that would not allow it to run at all. Also, if no fuel pump in tank, it starts looking like maybe the injector pump has an issue? This has happened before and affter a new fuel filter...but this is the first incident of total failure to ignite diesel.

 

[Rickstah]

OK, I found this thread below, is this what you use to wire up an actual assembly with A fuel pump in it? Is lift pump just another turn for what I received? Assuming I would need to find a pigtail plug that will fit the gasser fuel pump assembly? I feel like there are some more details it would be good knowing before I tackle this project...

2000 vw NB intank fuel pump wiring

As the title states, I’m putting a BEW intank pump into my 2000 NB and looking for some wiring advice from people who have done this on a New Beetle. I’m not using the location that is on the write up procedure for installing the relay by the fire wall where the coolant gp relay sits. I’m using...

forums.tdiclub.com

Just for grins, this is what distracted me from realizing my year was just a level sending unit

 

[J_dude]

https://s3.amazonaws.com/idpartsimages/pdfs/PDLiftPumpInstallGuide_v1.5.pdf

 

[Rickstah]

I wanted to explore a couple more possibilities for the abrupt change from wheezingly start to NOPE over one day and I recall having to do some major slamming on of brakes a few days before it failed. That was also before I was enlightened about "fuel level sending unit" instead of "fuel pump assembly" but I found some places where guys were able to drill out the check valve and get it going again, not necessarily during cold weather, due to some type of blockage.

I figure why not so I have looked over the couple of threads about it and it looks doable, the only thing I was soft on was a black inner o ring on the return tube, which I can see from the top of the assembly. The outgoing tube I see the crosshatch blockage being discussed as the target for the drill bit. I assume i should not be able to run a length of hanger wire through either of them but the image of the black ring looks odd, possibly broken. I need to go back and see if anyone drilled both tubes out but here is what I see, not sure what to make of the black o ring just sitting there. Any suggestions appreciated, especially after all the ones since I posted. At the moment I just want to get it running then maybe look into the lift pump kit on ID, thanks.

 

[pkhoury]

Ok this has been a little hard to follow, but looks like your old unit is the stock one for an ALH (no pump, just fuel level sender), the new one is for a BEW (has a lift pump). That is an upgrade, but I’m not sure if it will let fuel through if you don’t get the pump wired in though.

I’m not sure I understand, did the dealer install the new sending unit/pump and tank? And it was after they did that the starting issue began?

I think it still lets fuel through (the PD variant), as I didn't have issues when mine wasn't hooked up.

 

[STDOUBT]

Any suggestions appreciated, especially after all the ones since I posted. At the moment I just want to get it running then maybe look into the lift pump kit on ID, thanks.

I never messed with the return tube, but as for the sending tube....just drill, baby, drill!

 

[Rickstah]

Well for good or ill I drilled out the outgoing tube and after applying air it is slick and clear and a small black piece of gasket like material came out so I dunno. I noticed a Mongler post where he was talking about an o ring from the IP return port to the tank but it didn't sound like he meant the return tube on the sending unit. I did take a closer look and what I thought first was a broken o-ring looks like a fastened down o-ring or something, anyway, more reading to see if anyone drills out the return or leaves it alone because it possibly prevents fuel being used during a tipover...or maybe that is the black float on bottom, I need some salsa, lol.

 

[J_dude]

I’m not sure but I would guess the o-ring mentioned by Mongler in that post is referring to the common failure of the o-ring on the thermo-T fitting on the filter, not related to the sending unit.

 

[Rickstah]

I’m not sure but I would guess the o-ring mentioned by Mongler in that post is referring to the common failure of the o-ring on the thermo-T fitting on the filter, not related to the sending unit.

Thanks, Dude, I was thinking that after several more posts found. There is a slim chance that black gasket material like stuff I pulled out of there after drilling the fuel supply line was clogging, more likely it was something in-place the bit tore up. It got too dark and rainy but I took 5 gallons out so when I remove and replace tomorrow it won't be so dieselly in my car. Thanks for all the suggestions, everyone. Is there a hint in the fact I think I have observed it acts up when I am parked on an incline, and when it is level it seems to finally fire up? That indicates to me a low pressure situation that gravity may improve just a bit, I dunno, just glad tomorrow is Friday.

 

[Rickstah]

WELP! It is now back to its former glory before the wreck, lol, but dangit I am NOT POSITIVE what fixed it. I drilled out the sending unit to the pump and I think there may have been a gasket up in there or something, not sure, but a black piece of something came out. I also cleaned up the sender although the continuity rose steadily when I tested it from about 50ish to 245ish. I am more inclined to believe my belief when I first took the lines off the unit I could swear the blue was on the outgoing and black was on the return but nobody has opined what kind of delta in performance that would cause, which in my case was fuel starvation when trying to climb hills with my foot in it, intermittent just refusing to start and mid 30s or slightly less for my usual commuting around town and such when normally I was getting 39+.The acid test will be in the morning when it has sat all night I guess.

Thank you for all the help, now to see if eBay guy honors his "guaranteed" confirmation the unit I got (fuel pump) would fit, lol. Next job, finding shocks that will work with 2-3" lift in rear instead of the STOCK ones they put back on without mentioning it to me that go BANG when I hit any bump, lol.

 

[dieseldonato]

Ok this has been a little hard to follow, but looks like your old unit is the stock one for an ALH (no pump, just fuel level sender), the new one is for a BEW (has a lift pump). That is an upgrade, but I’m not sure if it will let fuel through if you don’t get the pump wired in though.

I’m not sure I understand, did the dealer install the new sending unit/pump and tank? And it was after they did that the starting issue began?

Yes they will let fuel flow through them. I had mine installed for about a week before hooking it up electrically. No real issues that I noticed, other then no fuel level gauge amd it was a bit sluggish over 3k rpm.

Well, disappointing but enlightening. The moment you mentioned it I realized what i had done, I was reading the manual from the gasoline engine section, not the diesel section, which explains why I posted all the gasoline fuel pump pics, lol. Embarrassing but I understand now, only eBay guy was so sure it was the correct "fuel pump" for my model TDI, even guaranteed it. I blame myself for misplacing that memory. I guess while I have it out I should try to do the sending unit fix to get back the almost quarter tank of delta on the fuel gauge from this sending unit. Thanks to all for clearing me up. I guess my problem still exists, the just deciding to stop firing up. This was a long weekend, lol. I am going to delete a lot of this crap I put up.

From personal experience, evilbay guys don't carry the right sensing unit. Went through it before I just spent the money at ID Parts and got the correct one. Collage is expensive....

 

[Marc Bourget]

Problem priming Injection Pump.

Not trying to hijack the thread but I haven't figured on how to start a new thread and I have a related problem.

Started with contaminated fuel. Replaced pickup. Eventually replaced engine. New engine will run using a fuel can. When placing a vacuum on the filter outlet to engine, I can draw some fuel with large vacuum, but taking the vacuum source away from filter outlet results in 5-6 seconds of "suck back."

Discussing the problem with Burpod is motivating me to install a BEW lift pump, but I'm not sure this will solve the problem.

The fuel diagram shows a breather valve (Item#7) up at the filler inlet. Can this be sticking or clogged not permitting "regular flow"?

Would you suggest something else?

 

[csstevej]

Go to the TDI 101 or your cars correct model and tap the red C lh corner of page , that will allow you to put a title in and then type your issue in the box below . You’ve now created a thread.

 

[csstevej]

Start a new thread , but to….

To answer your question, that breather was a carryover from the gas version , most people delet it , it will allow more fuel to be added to your tank . Look up fuel ventectomy.

Sounds like someone drilled out you check valve on the sender and an air leak further down the line is allo air to enter.

Chances are your thermostatic Tee is leaking very badly , try replacing the two o-rings and use Vaseline and lube it up really well and reinsert it.

 

[Marc Bourget]

If the Thermostatic Tee was leaking, wouldn't that relieve the vacuum created when I draw fuel from the tank?

By inspection of the fuel filler opening, the breather valve has a lever that's moved when you replace the fuel cap.

I'm going to repeat the priming operation tomorrow with the correct fittings (I left my Mighty Vac at home today!)