Cold Weather Design Flaw, Secret Recall from VW?

I twisted two pipe cleaners together and pushed that though the plastic tube. The spring came out with little effort.

This thread never gets old!

Just did this on '01 Beetle. "C" sender.

3 degrees F last week. Wouldn't start, so it didn't gell! LOL! Replaced battery and glow plugs. Two glow plugs were open. Ordered a set, one wouldn't come out, luckily it was a "good" one.

Did the check valve drill, while I was working on it.

Thanks TDIclub!

I got the sender out of the tank. Unsnapped the three clips, top of sender only came out part way. It felt like it was snagged. I didn't want break it and add to the gelling problem. I put it back together and in the tank.

Any suggestions on pulling the sender apart and the pick up and return tubes come off?

I confirmed I have the C version of the sender.

push clip broken what to do?

Hey all, great thread. I'm trying to get this done, but the little plastic push clip is missing from the fuel line going to the engine on top of the sender.
*edit*
There was a piece of the old clip still stuck in there, once that was out a pick tool released it.
I might have reassembled the spring/o-ring inside the sender with the o-ring facing the spring. (little sleep)
Will that cause any harm? What does that do?
I appreciate the patience with my dumb questions.


I flipped it back,
nvm

just rescued my 99.5 that was driving me batty by drilling that sucker out. thanks TDIclub!

I am having a problem with 2000 NB, where somewhere between 10 and 30 miles of driving the car loses power, not very responsive to the diesel-pedal, engine may die immediately, or might go a few more miles before the engine quits and will not restart. After a 15 minute rest, the engine will start again, but requires around 10 seconds of cranking.

Replaced air filter, fuel filter, and now this fuel gauge sending unit. The old unit was the "C", and the new unit from worldimpex is the "D".

I figured the checkvalve might be stuck or the entire unit might be super dirty and clogged. However, the old unit looks super clean - like new, and I just finished drilling through the checkvalve, put a thin screw driver through it a few times, blew through it a few times and now I don't see any little parts in the hole. I wonder if I got all the broken checkvalve parts out - I can't see any when I look through it, and I can easily blow air with my mouth through it. I reassembled it.

I am not sure if I will bother to install the old "C" unit which has just been modified, because the brand new "D" unit which I installed yesterday should have no dirt in it and should have a proper operating check-valve. After all it is brand-new.

BTW The main reason for this posting is to point out that - to the left of the part number is the Volkswagen four circles symbol. Above the circles in an arrow - this arrow points to one of the 3 screw holes - which holds the cover plate. It is the screw hole towards the rear of the New Beetle. My "C" unit was pointing exactly at this hole, and that's how I installed the new "D" unit. I think that screw hole and arrow combination is there for mechanics who are replacing the unit. That seems to be how it works.

It will take some driving to see if my problem is solved. If replacing the fuel gauge sending-unit doesn't solve my problem. Next I'll replace the relay 109. Many many years ago I replaced it with the newer Grey relay 109 as a preventative measure. I should of thought of replacing it as the first thing to do for this problem - but it really felt like a fuel flow problem. It might have been the ECU rebooting due to intermittent relay 109 failure. It probably boots in one second and during the reboot the diesel-pedal was not responsive. Another item is the crankshaft speed sensor - but a mechanic told me that always gives a check-engine-light and code. I only had the CEL at one of these breakdowns, and the next day there was no code for VagCom/VCDS to find. Maybe tomorrow I will buy another grey relay 109.

Update Oct 26th: I replaced the Relay 109. I drove 58 mostly highway miles with no problems. I don't know if it was the fuel gauge sending unit or the new Relay 109 which fixed the problem.

I plan in the future to reinstall the original newly drilled-out modified "C" unit when the fuel tank is low on fuel. Then keep the new "D" unit as a spare. I only had fuel gelling problems twice in the past 17 years, both times in unusually cold weather - figured at the time I needed to add more PowerServices into the tank, but it might have been the fuel gauge sending unit.

Well, it turned out the uneven choppy power was from an intermittently failing relay 109.

I drilled-out the checkvalve in my old "C" unit and installed it, taking out the new "D" unit purchased from Impex.

The "D" unit was in my car for a little under one month. I drilled out it's checkvalve. I'll see if I can sell it for a decent price. Otherwise I will just keep it in my garage as a spare.

Fuel gel balls

Fuel gel's in a ball at the site of the tiny intake?

Weird. sounds like gel could be replaced with emulsify, as alcohol is often sited as a anti gel component of these peoples problems.

A miniemulsion is generally obtained by shearing a mixture comprising two immiscible liquid phases, one surfactant and one co-surfactant (typical examples are hexadecane or cetyl alcohol). The shearing proceeds usually via ultra-sonification(tiny hole venturi effect) of the mixture or with a high-pressure homogenizer, which are high-shearing processes.

https://www.google.com/patents/US9310076

indysoto said:

Fuel gel's in a ball at the site of the tiny intake?
Weird. sounds like gel could be replaced with emulsify, as alcohol is often sited as a anti gel component of these peoples problems.
A miniemulsion is generally obtained by shearing a mixture comprising two immiscible liquid phases, one surfactant and one co-surfactant (typical examples are hexadecane or cetyl alcohol). The shearing proceeds usually via ultra-sonification(tiny hole venturi effect) of the mixture or with a high-pressure homogenizer, which are high-shearing processes.
https://www.google.com/patents/US9310076

Click to expand...

The check valve in the older revision sender units is restrictive and becomes the first victim in the cold due to ice crystals forming and stopping fuel flow. The latest version sender that I know if is version H. That's what I had in my 02 Golf TDI.

Properly winterized fuel won't gel at the temperatures people are reporting problems at. Usually the problems are due to ICING from water in fuel from condensation and not actually gelling. A clue is the fuel sender problem occurs at temperatures cold enough for icing but still too warm for gelling. People often think they have gelling but actually have ICING instead due to water. Properly winterized fuel can still have problems with water contamination from condensation. Free water in diesel fuel will destroy fuel system components (i.e., HPFP) in no time at all and absolutely must be avoided at ALL costs.

Things to do:
- Check fuel sender version. Should be Rev D or later, IIRC. H is the latest version that I know of in my 02 Golf TDI (Mk4).

- Replace the fuel sender with a Rev D or later sender, or modify it by drilling the check valve out of the sender.

- Fuel up ONLY at high volume / high turnover stations along major routes that get a lot of heavy truck traffic. Go where the big rigs go to get only the freshest fuel in the region and avoid getting fuel contaminated by water from condensation. Diesel fuel turnover is highest at these stations and is constantly being replaced, often daily. It is not uncommon for a busy truck stop along a major route to do more than $30k worth of diesel business in a single day. A favorite truck stop in my area gets an entire tanker truck (10,000 gallons) of diesel emptied there every day to keep up with diesel demand and to keep from running out. No worries about watery fuel at this station. Avoiding water is particularly important during winter months in cold areas due to condensation being more of a problem.

- Regularly use an additive with every tankful to take care of any water you can't avoid getting and provide some anti-gel in case the fuel wasn't winterized (unlikely at a busy station) and to help improve lubricity. My favorites are Howes Lubricator Diesel Treat and PowerService Diesel Fuel Supplement (white bottle). They do not contain alcohol of any kind. Additives containing alcohol are not to be used at all because they will do the same damage that water does.

- Fuel quality is ABSOLUTELY EVERYTHING when it comes to ensuring long life and reliable service from the fuel system (HPFP in CR TDIs, rotary IP in older TDIs, PD injectors in PD TDIs). DON'T put crap fuel in it, especially during winter months in cold areas.

Good luck.

Thanks for the info club members. I just drilled out the hole, took out the ball bearing&spring. works perfectly now.

Bump of this thread.
I am getting a lot of calls that will probably pertain to this problem.
See page ONE