Nissan Micra problem with the fuel pump floater

[alexzaki]

Hey there guys!

Well the last 2-3 days i've been running around with the car and everything was OK. Today i noticed that the fuel gauge dropped under the red indicator and the warning light didn't come one. I thought there's something wrong with the fuel warning lamp so i filled a 5L bottle with fuel just in case and started driving around to make sure it will light.

Well it didn't. I ran out of fuel. I checked the fuel warning light and it was working OK as i put it in another place in the gauge cluster and it lit up. I started thinking that there is probably something wrong with the fuel pump floater. I striped the back seats and played with the 2 connectors connected to the fuel pump. One (the smaller one) is powering the fuel pump which works perfectly and the other one is probably for the floater thingy. The connector has 3 pins probably (GND,+,+). One plus probably moves the fuel level indicator which works perfectly and the other plus is probably the signal line for the fuel warning light. I made a contact there and the fuel warning light came on.

There is probably something wrong with the floater thing. Any ideas what often goes wrong there? Tomorrow i will take the whole fuel pump outside and check it so i'd be pleased if anyone could give me iNFO on what to be aware of.

This is probably what i'll find tomorrow:

Thanks guys,
Alex

 

[frank]

i think the light sensor is a separate little fitting, and not part of the float rheostat alex

 

[alexzaki]

And where should that be? I mean where should i look for mistakes? As i said when i made a contact on those pins on the fuel pump its self, the fuel warning light came on - so now i know the wiring, gauge cluster and light works pefectly. Shouldn't the floater make that contact somehow?

 

[RR_dev]

No, it's a small moisture sensitive resistor that activates the warning light. When it's dry, the resistance changes and the light comes on. It's part of the sender unit, but nothing to do with the float

Replace the sender unit and it will solve your problem.

And don't short out wires when you have an open fuel tank unless you wanna BBQ yourself...

 

[alexzaki]

Mate, we are talking about the K11 prefacelift year 1994. I talked to Nissan main dealership, and he said it's all mechanical stuff. If you check this pic out:

You can clearly see the potentiometer connected to the floater thingy. I'm going to stip it out now and will report later.

Alex

 

[frank]

there are probably different types alex, someone posted a pic of theirs a while back and it had a separate little silver capsule that was wired to the light

 

[pollyp]

this is the moisture sensitive resistor capsule

 

[alexzaki]

Jup, i didn't notice that untill i took mine out today :doh:

Pics:

Here is the whole floater thing:

The potentiometer which is workig fine (regulates the fuel level on the gauge cluster):

And here is that capsule - the moisture sensitive resistor which aint working (makes the low fuel warning light turn on):

Guess the guys at the main Nissan dealership ain't got a clue what they are talking about :suspect: :glare:

They want so sell me the whole part in the 1st pic for like 250 euros, they are probably high lol :laugh:

Ok, i visited a scrap yard and found nothing. Then i checked some ads and found a crashed 1993 1.3 Micra - the guy is selling it for parts. Mine is 1994 but also 1.3, so the parts are swapable probably right?

Thanks guys,
Alex

 

[pollyp]

i remember they were the same mechanism & plugs on my 98 slx and 94 slx

 

[alexzaki]

I guess i will give it a try by the end of the week The guy selling his crashed Micra hasn't got a clue what im talking about lol. I told him no problem, i will come and strip it out myself :grinning: Probably 99.9% it will fit as it's only 1 year in difference but who knows.....Nissan always fiddles with strange things :laugh:

 

[frank]

bear in mind that not all k11,s have the warning light tho alex

 

[r-reg-sr]

i had fitted a facelift k11 fuel pump when the 93 lx one gave up IN 2003
and i can tell you the pump itself is half the size and weight of the older ones------thats for all you weight reduction guys9hint) yes the pump had the same wiring for my 93 lx
and why rely on the fuel light to come on? when your neeedle gets to just above red mark=TIME TO TOP UP!!
GOOD GIMME IK THAT LIGHT

 

[alexzaki]

why rely on the fuel light to come on? when your neeedle gets to just above red mark=TIME TO TOP UP!!
GOOD GIMME IK THAT LIGHT

Because i can't stand knowing that something ain't working 100% on my K11 :laugh:

bear in mind that not all k11,s have the warning light tho alex

Frank, you mean that there's a few K11 around not even having the low fuel warning light? I actually asked that guy selling his crashed K11 and he told me, that the low fuel warning light is working when the fuel level drops. This means that it has that same mechanism as mine, don't you think?

 

[r-reg-sr]

if the needle goes on red and you dont fill up guess what isnt working?
unless you youst to spar with tyson back then-------its called human error

 

[frank]

its probably just the base models eh alex, my misses,s 1.0L and my dot dont have the light

 

[alexzaki]

The crashed K11 is the LX model, same as mine just one year older. The guy said the low fuel warning light works, as it lights up when he was running low on fuel. I will give it a go, and go check it tomorrow after work and see whats what (Y) Will report back...

Thanks guys,
Alex

 

[r-reg-sr]

nice
hope its succesfull

 

[alexzaki]

Hey guys!

Just wanna inform you, that i went yesterday after work to see that crashed Micra. He hit a Clio and the front of the K11 looks in bad shape although he hit it while going only 40km/h
I took the floater part and it was a straight fit on mine. The new part shows correctly the fuel level on my gauge which means that the potentiometer on the new part is working OK.
Now, i just have to wait and see if the low fuel warning light will pop up :laugh:

I also took one door handle as mine was cracked looooooog time ago :grinning:

The guy was very kind. He told me i can come back anytime to take any other parts :laugh:

 

[alexzaki]

Yeeeeeeeeeey :laugh:

Mission accomplished (Y)

Greetings,
Alex

 

[Shaun]

Just to add i don't have a low fuel light. :laugh:
Happy it's sorted though! (Y)

 

[Shaun]

Just to add i don't have a low fuel light. :laugh:
Happy it's sorted though! (Y)

Yeah that's right i'm quoting myself.
Found out i do indeed have a fuel light but it doesn't turn on and don't want to run it empty for the sake of it.
Anyone know how low you can go?
Pictures would be lovely (i know there is probably a variation too.)

 

[r-reg-sr]

used to get 50 miles outa the old 1..0lx=---from when the light came on

 

[alexzaki]

Shaun, you can see my fuel indicator dropping little under the red indicator and that's when my low fuel indicator light poped out :laugh:

But as you said there is variation between gauges. My original LX gauge showed the low fuel light before the fuel indicator reached the red indicator.

I suggest you better get yourself a 5L canister and fill it with fuel and just drive hehe :laugh: