AndyPandys Sender Mod, can give VAG HP at high rev.

[NarfBLAST]

A mightyvac is nice but I don't think it is absolutely neccessary when changing a fuel filter... I just made sure I have some diesel in fuel can to fill the new filter, I popped all the lines back on and started her right up. I hope the sender mod goes as well... there was no mention of "bleeding" in any of the posts. I will be sure to post with an update!

 

[NarfBLAST]

Did it! Love it!

Fricking awesome! Both kids were asleep, the sun was still up, the wife was okay, and I had a few minutes alone with the car, FUEL SENDER MOD TIME!

Tank was a little under half full so the "lower bowl" of the fuel sender was full but I just tilted it and let most of the fuel drain back into the tank. I had a paper towel to catch the drips and an oil catch pan ready to put the sending unit into... no mess!

Once the unit was out and in the pan the FIRST thing I did was to remove both wires from the level sensor track connectors so that I could leave the lower bowl (which still had fuel in it) in the pan and take just the very top plate with the two tubes off. Sweet! No mess again!

Found a tight fitting drill bit and it only took a few slow turns to destroy the white plastic tri-pod seen when looking from the top... then I took a coat hanger and started fishing... I got the spring out no problem but the black rubber flapper, which is much bigger than the tube, seemed to be able to "hide" in a wider part in the middle of the tube where it used to seat with its spring... I didn't use any compressed air, just blow hard with my lungs from both ends. And the coat hanger to fish the spring only slightly twisted and black rubber flap in one piece! I highly recommend going slowly and only just breaking the plastic tri-pod using a few turns of a clean drill bit so that you can remove the spring and round rubber flap in one piece, less worries that way.

I was kindof nervous and in a hurry so I reget not taking pictures nor hooking up a vacuum pump and gauge to check the amount of vacuum required to break the check valve... I did do the suck test and there was alot of resistance to air, image how much to fuel! Not any more!

So the test drive! Fricking awesome! My car has 296,000 km and is mostly stock except for PSI powerbox, and egr valve that won't open (oh well, scanguage clears the CELs when they appear), and a new VNT actuator that is adjusted for quick spool up on the stock VNT15). Power used to plateau at 3500, but after drilling out the fuel sender: the power builds smoothly right up to red line! Remindeds me of when she was brand new! You can really feel it in second and third gear, revving it up is fun again! Also, even at 2000rpm the throttle seems more responsive and even less turbo lag it seems!

I have a butt-dyno from this March, when the fuel was probably thicker. My car ran alot better when the weather got up over 15 degrees celcius, so I suspect this mod will really pay off next winter when the fuel gets thicker. When I get a chance I will run the butt-dyno again, but for now I've penciled in my perception of the difference in my car...

Also the old dyno pull was in 2nd gear, sampled at .8 samples per second that is not really much data, but you get the idea... power used to plateau at 3500rpm... as I have illustrated using mspaint now it pulls right to redline!

Thank You AndyPandy for reviving this mod for 2008! Fricking awesome! Also thanks to folks who did the other threads, I read every one I could find on tdiclub and the payoff today was fantastic! Oh by the way, I had the "D" revision part number in my 2001.

 

[ChadMC]

So for the people who have done this, have there been any bad side effects from doing this mod? Are there any down sides to doing this? I'm thinking about doing this soon.

 

[NarfBLAST]

Hi Chad,
I've had no problems yet, I will try and run a butt dyno tonight for an update. I've had no problems after 3 weeks she is still running great, hence the video in the sig below. This mod has put the most smiles on my face of any mod so far and it didn't cost anything!

I still have bubbles in the clear line (had them before this mod)... bubbles are supposed to be normal. Got a new themostatic tee to try soon, maybe my fuel lines have tiny cracks that let in air but don't quite let out fuel yet? Also the top of my fuel filter is always wet? (was like that before the mod) Maybe I will pull the line from the tank off when I change the tee just to see if drilling out the check valve will cause the line to empty into the tank and see if this causes a starting problem... since my last post I bought a mitivac type device (with brake bleed bottle) and a oil extractor so I will have two priming options in case cranking doesn't work! Will post an update.

 

[NarfBLAST]

Drained the water separator today. Forgot to close the knob before starting the car. That was interesting! Diesel fuel puddle under the car. Then ran ran for about ten seconds before it drained the fuel filter stalled. How or why did I start the car before closing the water drain? It happened like this:

When I opened the water drain on the fuel filter, nothing came out! Maybe this was due to the deleted check valve in the sending unit in the fuel tank? Anyway, I had to remove a hose from the top of the fuel filter to equalize the pressure so that fuel would drain out the bottom. After draining about 30cc I figured I had nothing but diesel (no droplets) so stupid me I put the hose back on the top of the filter and it stopped draining so at that point I totally forgot to tighten the separator knob! Started the car, ran for 10 seconds then stalled. I pretty quickly realized what happened when I saw the clear line was full of white foam and there was diesel splashing under the car. I felt pretty stupid. Afterwards I figure my fuel filter was empty so I used my oil extractor to pull fuel up into the filter. That worked fantastic... had to crank for about 15 seconds to clean the air out of the clear line. It was really strange the way it GRADUALLY started... kinda smooth and really weird. Ran fine the rest of the day (100km).

Anyone else done the fuel sender mod and then had trouble draining the water separator?

By the way, I did not find any water. I have been told that it is not neccessary to drain the water separator?

 

[andypandy]

Anyone else done the fuel sender mod and then had trouble draining the water separator?

By the way, I did not find any water. I have been told that it is not neccessary to drain the water separator?

Well i have drained my fuel filter twice after the mod.
(I have fueled my car with old diesel from a farm tank that had some water in it)
Anyway, i just loose the holding screw and pulled up the filter a bit and drained it a few sec with no problem untill it just was pure diesel that was dumped.

 

[andypandy]

Conclusion update

Well, what have happend since the mod..

VNT2052, 2.5" downpipe-cat, FMIC + all pipes.

Still the same Evrymod and diode boost mod where I push the original pump and nozzles to the max.

(Yes i shall shift nozzles some day)


And the car goes quite well i would say. Before this change the car was like 7sec to 60mph and after.. a little faster and I can set the boost to so low as 17-18psi(1.2bar) without any smoke.
(because a more free flowing system now at all parts around the engine)
Maybe under 7 sec now.

Before it was actually close to 21-22 (1.5bar) in the IC with free flowing pipes and vnt15 i realize after wards and was smoking at WOT. (moved the mapsensor)


Come on to the point then!
Everyone is talking so much about these lift pumps and the difference after wards.
Well i got a real difference with this thread mod above.. could it gain more power with an lift pump adding to this?

Installed a 7psi (0.45 bar) lift pump with more than enough flow 2 days ago and have drive the car quite much these days and push it real hard.

So tell us about the difference then
Well the car is already max responsive with my 2 step evrymod as it possible could be.. so there was not much difference to gain there.

Was it more power in the upper rev band?
Very little.. some maybe... (a little dissapointed here)

I should say like this... in my car.... where total change=100%
- drill out the narrowing valve was like 80%
- A lift pump on this.. well.. 15-20% off the teh total difference


So, a Lift pump from scratch is quite a change.
But Drilling out the sender mod.. and get rid of all bubbles, taked me, with this car and mods, very close to that level without any lift pump.

 

[mojogoes]

Does every one who did this mod feel it gave a positive benefit after they did it.........responses from those who did this mod most welcome.

 

[shizzler]

I did this mod following the directions in the other thread pertaining to correcting the fuel gelling stalling issue. Mine didnt have the flapper, the but the pastic grating was still in there. What the hell was VAG thinking when they put a restriction like this in a diesel fuel sender with NO lift pump.

Anyway, easy mod, my butt dyno said 3-6 HP above 3700rpm.

 

[mojogoes]

Cheers shizzler!........mines an old A3 1z sender so i guess it will be worth doing even though i have fit a lift pump (in the engine bay) but i agree with you about the VW comment though i'd wager a bet that they used a sender that was ready available off the shelf more than anything else.

 

[Lug_Nut]

The A3 and B4 (at least the ones here in the states) don't have the restriction and therefore nothing to be gained by opening up the tank only to close it up again.

 

[im570rm]

Not that fast. but not that slow either for a diesel.
This is only to show what can be done with a stock 110hp car without any major changes.

2052v fmic etc etc no majore changes...it's almost bone stock...lol

 

[brightsideteeem]

how do you disassemble the sender to drill the hole through??

 

[mojogoes]

Lol go back to post 1............doesn't this show the "how too!"

 

[brightsideteeem]

no, i know how to get it out and everything.

I mean how do u disasemble it, how do you take the top part off that moves?
Just pull?


( i have the sender unit out of the car)

 

[brightsideteeem]

i figured it out in the end lol

It has made a noticeable difference, quite surprised really. Car seems alot more eager throughout the entire rev band, but especially over 3K rpm.

Engine seems quicker to pull, under load, above 3K rpm where as it was slower before the mod.

Very pleased, and as said: "didn't cost a dime" lol

Thanks for the help

 

[mojogoes]

What year is your car brightsideteeem?

 

[Jasengine]

I did this tank mod about 15 months ago and never looked back. Engine revs past 4000 no problem, where as before this mod 4000 was a stuggle
! Can't loose really with is little modification...

 

[Jakobicev]

Does every one who did this mod feel it gave a positive benefit after they did it.........responses from those who did this mod most welcome.

I did mine today and i agree that it has made a difference especially over 3000-3500 rpm.Pulls quite fine now.Until now the fun was over at 3800 rpm so there was no need to push it over.Since the cost is 0 %,i needed only 15-20 min to drill-clean and connect it back to my car and there is a little improvement I,m happy.

But no matter how big the hole now is i don't think there are some Hp more at the top speed,i took it for a run on a speedway some hours ago and the top speed was 190 km/ at 4100 rpm,same as 2 week's before without this mod and the manifold was not cleaned yet at that time.
Thanks for the tip's!

O,i forgot almost,my sender part number end's with a letter D so if anyone has the same type,yes it helps !

 

[Gothmolly]

Is the model H sender definitely, absolutely the fix for this? My 02 golf has dismal cold-starting performance, air bubbles in the fuel line, and mediocre performance.

 

[That Guy]

Thank fricking God for you guys....I've been troubleshooting a related issue for weeks. Trying to track down what the problem is.
I have an 01 golf with a butt load of recent upgrades. Works great unless I WOT...then stumbles at about 3500 rpm and then although I can get it up to the red line it has inconsistent issues after that. And it only seems to pull air into the line when I push it up there otherwise it's bubble free.

I've got a few other things to check, replace, and clean...but this sender issue sounds like it could be a big part of my problem. (I was going to have a look at that and clean the lines anyway.)

I'll have to check maybe tonight after I get home.

Just out of curiosity what makes the H model better? Is the hole on it unrestricted?

And I'm not sure this was answered 100% yet....but why is this built this way to begin with? There must be a good reason or they wouldn't have done it. I don't suppose any VW engineers frequent this site?

 

[That Guy]

Update...

I installed the rev H of the sender and cleaned the lines.

The problem is now gone. I can get it up to the red line with no noticable issues....VAGCOM data shows a nice power curve too.

I do still get a Inconsistent Timing cel if I push it up there, but that has to do with the IP not being able to handle the upgrades and/or it's got some minor problem. But that's another story.

Thanks again guys! :-D

 

[mikey141414]

Thanks for the how to! I did this today and am very impressed with the throttle response and lack of air bubbles. I greased the fittings on top of the tank with grease and I figure that was what stopped the bubbles, but the mod has definately made a change in the throttle.

Next up, EVRY mod!!

 

[Liamhorsley]

I ahve the 90bhp tdi golf, got a every mod on it, but i have also noticed a few bubbles ? Should i bother ?? i dont have injetors ?

 

[MoldovaDIZEL]

i want to applaud the OP for this post and DIY, this saved me so much headache and money! thank you so much.

car runs like never before, revs so high,so clean, 90% of the black smoke is gone too!

 

[Kevinski4]

Some good info in this thread!

 

[MoldovaDIZEL]

this has to be the first people do, bevore ccv, venectomy mods, mufflerectomys and so on, cant believe i only heard of this now....when i started having issues. this should be a sticky!

everyone should do this with ALH. of course better is a lift pump, but this is free, and wow what a difference, car is quiet as well, for sure the injector pump is wayy happier.

 

[Mike96ZJ]

Got linked to this thread from another one, but I am definitely going to have to check this out now.

 

[yseent]

Hey Guys,

A little confused on this post. I got the sender unit pulled out, and comparing mine to the pictures, it looks like the OP drilled out the check valve for the return line, which according to this post (and others I've read) will cause problems. I've based this on my understanding that the "tee" in the fuel filter, is the fuel return line to the tank, which is BLACK, on the sender unit it is located on the left, and the BLUE on the right is the delivery line. Am I wrong here when I see that he has drilled out the delivery line check valve (on the left side??)??

 

[Torque!]

Done and Done. Getting the retainer ring off the unit was a major pain. I used a wood block and rubber mallet..a little ata time for 5 minutes until it started to move. The rest was easy.

Thankful for this resource. My TDI doesn't sip through a restricted straw anymore.