BMW E30 fuel level sender sending unit function, failure and repair

[@baroquemedicalitsupporttea8306]

Felt like I was at a mechanical school. Thank you for the awesome academic elucidation of design and function. It gets easier when one knows design to repair it ! I have an E23 BMW 735i, I think it shares same design as the E30, with non- functioning gauge. I will attempt following your lecture, to repair it. Sonny

[@e30base95]

Thanks for the comment!

[@trevord3903]

A very helpful video on this topic; meticulous and detailed. Thank you for taking the time to post it. Good to understand the electrical circuitry schematic. Cheers!

[@derwynoxley7247]

Hi, Just a quick note - I had a n intermittent fault on the main sender (mine is only 1 x sender). To remove the oval shaped tube I drilled holes in one edge of each crimped recess. I was the able to insert a small screwdriver and prise the remaining crimped section proud of the top housing. The tube slid off really easily and there was sufficient material left to re-crimp once done. I was able to clean the inside with brake cleaner aerosol and took some very fine grit paper to the wiper contacts on the float as well as the empty level switch contact faces. Back in the car and all looks 100% again.

[@NickDompierre]

Awesome I will try this. Thanks!

[@enesfazlic6017]

Thank you very much you helped me diagnose and fix my problem.

[@bridges5659]

Great video. There is a way to replace those 2 thin wires. Nichrome wire that's found in hairdryers, modern heaters, should do the truck. If you apply tension with a snipe nose plier and solder, you can be successful. You will need someone to assist you, four hands. Some of the E30's needs a full tank for the sender to work. Mine does that, ensuring that I had a full tank all the time. As soon as the Guage drops, I fill the tank up again.

[@asmarasmar1936]

السلام عليكم اذا سمحت كيف يتم توصيل اسلاك عوامة خزان الوقود لمرسيدس ١٩٠ بالقاعده السفلى او رسم الاسلاك من الأعلى إلى الاسفل وشكرا لك

[@moza260]

it is really helpful, i wanna try it myself and maybe try to buy a cheap multitester meter, but how do i set the multimeter?

[@Falkenerei]

Very good...congratulations well explain

[@vwlippy]

This was very helpful. Thank you!

[@tinohyland5312]

Thanks! Very Helpful.

[@e30base95]

If you find this video helpful, please like, share and subscribe. Thank you!

[@c.4e39]

Hello brother, I have a problem with the fuel gauge in my car.e30 The fuel gauge is random and not correct at all. Sometimes the fuel light glows even though the tank is full. Can you help me solve it?

[@robi4387]

Thanks for this. I have a 1988 320 made in October delivered in November. It has a 63L tank - I didn't know some earlier ones came with 53L that might have given us range anxiety ;) Now I have a jumpy fuel needle (a bit like evanarends7825 three years ago) but mines is showing 1/4 full to empty when I think it should be fuller, but maybe some leaked out or evaporated!? Maybe the sender is wrong and it is 5/8ths, hmmm. Time to go in there with a multi-meter. Update/progress: So, I lifted the rear seat base and the sound padding to find the oval (R/S 4#philips2) and round (L/S 3#philips2) covers, removed them and...tested 66ohmn and 75ohmn steady and when I reconnected fuel gauge steady BUT when I banged the floor the needle flickered. I pulled two wire connector of the second (L/H) unit and popped in two wood screws to make contact, and banged again - needle solid this time. So, my fault lies in the second (L/H) fuel gauge. I know what AUF and ZU mean.... they mean Oh! F~~k! the O-ring seals are shot/flat/cracked. Sigh! OK found genuine seals and filler cap seal on eBay. The central rod was quite rusty - problem with ethanol in fuel methinks - cleaned with knife, 280, 400, 1,000 and 3,000. One pass of the 3000 on each side of the two wires and crossed fingers. Fuel needle steady for now, but perhaps should replace the rod with stainless steel rod?

[@szlaeyer22]

I have a 1986 E28 518i with a 70 liter tank. When I fill it up it actually shows just 40 liters on the guage and starts showing empty when half of tank is gone. Have you ever encountered this? Any ideas if that unit is fixable? Thanks.

[@chillyE30]

I’m doing a early to late fuel tank swap . I’m about to wire in the secondary (driver) fuel level sender . I would just splice into the green/brown wire which is labeled (G) on your diagram for the gauge and wire it over to the driver side level sender on both connectors ?? That would be in series ? For anyone doing this you also need to have a late model fuel gauge(63L) in the cluster because they are 120ohms and the 53l fuel gauges are only 60 ohms .

[@akuab2]

Hello. Do you know what wire is used on sending unit. So I could replace it with the same resistance. Thanks

[@ethanfrank6750]

What guage wire does the unit use?

[@mimariposa5027]

How can I remove cover of unit

[@vincepratico]

Please specify, "Special resistance wire". Thank you

[@andrespot]

Hi, How can I solder back the thin wire to each contact? It seems each contact point has some kind of resin, so I couldn't solder the wire with a regular solder iron and soldering tin

[@e30base95]

They are just regular solder joints. You probably need to clean the contamination off the joint first.

[@evanarends7825]

Hi therw E30base please can you give me advise. When I fill up my e30 325i the fuel gauge goes to full but after I drive it moves up and down, (jumps around) then maybe after a while it would just lay at the empty mark until it decides to jump around again. However the light which indicates empty does work and goes on when car fuel is low. Thanks in advance

[@e30base95]

I will check the resistance between C2 pin 2 and C2 pin 16 in the back of your instrument cluster first to see if there is a good resistance signal from your fuel level sender to fuel gauge first. Then figure out if the fuel gauge, the fuel level sender, or wiring is at fault.

[@ic2306]

how did you remove the aluminum enclosure on it?

[@e30base95]

Unscrew the button bolt. I clamp the top horizontally on a vice and carefully wiggled the casing back and forth to remove the casing.

[@kostasgeronatsios2945]

i have to know how the hell you got it out

[@ransg4395]

Hold the top hard base on a bench wise. Remove the bottom nut. Then twist and wiggle the aluminium tube slowly and pull.