Replaced both Fuel Level Sensor/Sending Units. DIY with pics....

Fuel sending units & level sensors replacement

Here are the symptoms my car had that prompted me to replace my fuel sending units & level sensors:

1) Car died on the freeway even though CPU said I had 45 miles till empty.
2) Then it did it again even though CPU said I had 75 miles till empty a week later.
3) Car stutters while accelerating at full throttle, even in straight line.
4) Rough idle. When taking car out of gear coming to a stop, needle would dip below idle, sputter, rev itself back up, only to dip again and eventually die sometimes. I could fire it right back up, but just ANNOYING.
5) Poor MPG.

SO, I decided to replace both sending units/level sensors. I also replaced the fuel filter.

Fuel sending units & level sensors replacement:
NOTES: I AM NOT RESPONSIBLE FOR ANY DAMAGE. THIS IS SIMPLY WHAT I DID. WORK ON YOUR OWN CAR AT YOUR OWN RISK.
That being said, I had about 3/4 tank of gas in my car at the time. It's suggested that you wait till you are basically empty before you do this job.
HAVE A FIRE EXTINGUSHER HANDY. Although if my gas tank caught, I don't know what good the tiny extinguisher would have done. And finally, use your brain. You're working with fuel here, so don't smoke, don't use a working lamp that gets hot, etc.
Again, I am responsible for nothing, this is just documents of what I did.

1) Disconnect battery.
2) Open your gas cap.
3) Remove rear seat bottom by pulling up on the front edge of them and then lift the whole bench up and out. In the first pic, you can see the sliver tab on the driver side where it was holding the seat in. Just lift at that spot and it will pop off.
4) Lets start with the passenger side.


5) Lift the rubber grommet that seals everything up.



6) Now lift the big rubber flap covering the access panel. Remove the 4 nuts holding the plate in place.


7) Unplug the electrical harness. It's a sliding lock harness.

8) FIRST (1 on the pic), remove the hose clamp. This thing was annoying so I shoved a small flathead in the loop, pried it loose, and used a needle nose plier and just ripped it off. SOME gas will spill from this hose, so be ready with towels. I shoved a big bolt in the hose to keep it plugged while I worked. Replace the old hose clamp later with a standard, flathead-screw-closing hose clamp.
9) SECOND, (2) remove the ring that secures the fuel sending unit in place. To do this, place a flathead screwdriver on the raised ridge on the ring, and if you want, have a buddy do the same thing on the opposite side, and at the same time, both tap the screwdrivers with a small hammer. It will take a few good whacks to get this sucker loose. It only takes about half a turn to get this ring off. Turn in COUNTER CLOCKWISE direction to remove.


10) Once the ring is off, you will have to give the unit a good pull, but it will pop off. Stand by with a bucket to put this in as it's covered in gas.



There will be a rubber gasket that comes off. Replace it with the one that comes with your new pump.

11) Put the rubber gasket in place first. Then slide the new fuel unit in place. Push it in so it's all sealed and in tight. Replace the ring to seal it and hammer it back in place, opposite of how you took it off.


12) Re-connect the hose using a new hose clamp.
13) Re-connect the electrical plug.
14) Put the plate back, bolt it back up
15) Put the rubber flap back.
16) Put the rubber grommet back.
17) DONE. Move on to the other side. Drink a beer here. DON'T SMOKE anywhere near by.

OTHER SIDE (Driver's side)
Basically, everything is the same EXCEPT there is a connector on the bottom side of the unit that you have to pry off the old one and plug into the new one. Here are the pictures:
1)

2)

3)

4)

5)

6)

7) OK, here is the part that was connected to the UNDER side of the sending unit. You have to pry it off (one push tab connector and then used a flat head to pry it off. It's one piece)


8) Here's the new unit installed. Re-install the electric harness, the hose to the connector with a new hose clamp again, and finally the ring to secure everything.


9) Put the black top back and bolt it down, cover it all back up, put your seat back in place and you're done! Don't forget to put your fuel cap back on, re-connect your battery, and make sure everything is all cleaned up.

10) Time for a test drive!

Just so everyone knows, ALL of the symptoms I listed at the beginning of this post are now gone in my car. No more rough/dying idle, no more sputtering, just a smooth power band, and finally, I drove the car to 15 miles to empty and it was still running fine! I have not run it down to zero yet, but I'm just happy the way it is.

Thanks and good luck everyone.

-Toby.

your on a role today. ill need to do this soon

nice writeup!

how long did it take? how much? any special tools?

Took about 45 minutes for the first side just cause I had no idea how to get that ring off. After that, the other side took no more thank half hour.

No special tools required. Screwdrivers, hammer, socket set....that's about it.

Good luck!

hey, thanks for telling me about this DIY...My symptoms are exactly what your car was going through.

How much are all the parts?

Originally Posted by FRANCO

hey, thanks for telling me about this DIY...My symptoms are exactly what your car was going through.

How much are all the parts?

Glad my write up shed some light for you. I hope you get your problems resolved.

I got my parts through from a friend in high places..... So I'm not sure how much the parts will run you. Hope it's not too bad!

Ok so you replaced...

Fuel Filter. Part # 13 32 1 740 985 KAYSER
Fuel Tank Sending Unit Left Side. Part # 16 11 6 768 788
Fuel Tank Suction Device Right with Main Fuel Pump and Level Sensor. Part# : 16 14 6 766 942

Did you use any o rings or additional seals?

Nope, there is only really 1 gasket per side and they could have been re-used, but regardless, the new units came with the o-rings.

Originally Posted by TKC

Nope, there is only really 1 gasket per side and they could have been re-used, but regardless, the new units came with the o-rings.

So then the list I have is what you used? Around 350 in parts?

And some new hose clamps. Yep, that would do it.

Price I'm not sure about....I got a hook up on them so not sure what retail is.

My diagnostic thingy gives a error from the sender unit ocassionally, and until I cleared it I was having crappy gas mileage, and while I was in neutral idling, I'd watch my avg mpg drop.
So far its been ok. I don't have the stalling issue. I think I might just replace the sender one of these days.

Great write up. Good pics. This should be added to the DIY collection thread for sure. As a lot of early E46s have this problem.

was the fuel filter in there somewhere? if so at what step or is it all one piece?

Originally Posted by petscan

was the fuel filter in there somewhere? if so at what step or is it all one piece?

Fuel filter is under the car. He did not provide pictures for those steps

ok i read all the steps and thought is it me or am i just missing it. was thinking of changing mine out but did a search and didnt find a diy on it

Originally Posted by petscan

was the fuel filter in there somewhere? if so at what step or is it all one piece?

Originally Posted by Twin_Guns18

Fuel filter is under the car. He did not provide pictures for those steps

Originally Posted by petscan

ok i read all the steps and thought is it me or am i just missing it. was thinking of changing mine out but did a search and didnt find a diy on it

I left out the fuel filter replacement steps because there's already tons of DIY's on how to do it.

Here's one to help save you time. Good luck!

http://bimmerinfo.com/diy/fuel-filter/

Ordered parts tonight. Going to be doing this. My baby has been giving me some hicups below 1/4 tank

Originally Posted by Twin_Guns18

Ordered parts tonight. Going to be doing this. My baby has been giving me some hicups below 1/4 tank

a quick tip when putting the unit back, put the gasket in first then drop down the sending unit/pump in, otherwise it won't go in.

Originally Posted by SL Blak Soldier

a quick tip when putting the unit back, put the gasket in first then drop down the sending unit/pump in, otherwise it won't go in.

Thank you.

What should I do to precaution against fires or explosion? I heard people grounding themselves, using concrete tools, etc? Can you please explain.

so is this the fuel pump I assume? I just see fuel sending unit but I didnt see him mention or say fuel pump. Is this what hes talking about?

Great write up...piece a cake! 30 minutes - metal retainers a bitc*!