Fuel guage problems

Affiliate Joined: 28 Jan 2005 Posts: 360

Does anyone where the R19's fuel level sender is located or am I correct in thinking it's part of the fuel pump?

Our conversion is nearly complete now with the exception of a functioning fuel guage and whilst it's seemingly not essential to some people it is annoying the tits off of me so could someone please fill me in on the secret as I can only find three wires which go anywhere near the fuel tank (a green and two whites with grey stripes).

Cheers,

Mick

FCS Event Manager Joined: 04 Jan 2005 Posts: 3680

in the boot, lift up the carpet and u should see a large rubber cover, prise that out and the fuel gauge sender unit is under that.

Retroholic Joined: 12 Feb 2004 Posts: 5685

What neo says for the tank end. Dash end i'm not sure but its listed in the 19 haynes what the 5(iirc) wires are for

Affiliate Joined: 28 Jan 2005 Posts: 360

Oh bugger it! Cheers for the info WN but its left me rather stumped.

So any clues on how the sender unit works? Obviously it's some kind of variable resistor but i'm getting no joy from it and it was working fine before the conversion. There are four wires which go to it... Obviously one is the live feed for the fuel pump so any clues as to what the others do? I've tried putting power to them but I get nothing back to indicate a fuel level.

Mick

Retroholic Joined: 12 Feb 2004 Posts: 5685

The fuel pump is a seperate unit, the 4 wires are for the sender only

Bet that adds to the confusion more Smile

Affiliate Joined: 28 Jan 2005 Posts: 360

Yep, indeed it does Chet and to add even more to the mix the other end of the loom isn't 19... it's a bastardised Megane loom Razz

According to the Haynes wiring schematic there should be a mauve/purple wire somewhere on the 19's sender unit but I can't see one under the rubber cover anywhere. Both the 19 and Megane looms require 3 feeds to the senders according to their respective schematics but I just can't seem to get it to work. I've not come this far to be beaten by a bloody fuel guage!

I take it the fuel pump is a seperate yet simple On/Off type circuit Chet and in the event of a bump or crash the inertia switch cuts the pumps power?

Mick

FCS Event Manager Joined: 04 Jan 2005 Posts: 3680

What type of fuel gauge do you have on the dash?
analogue or the digital fuel computer ?

Affiliate Joined: 28 Jan 2005 Posts: 360

Well THIS is the car in question and it has a standard Renault/Velo electronic fuel guage which is fitted to in the DASH.

Now my way of thinking is that in order for the fuel level to be displayed by the guage the guage sender in the tank needs a 12v feed and an earth. The sender, once powered, **SHOULD** send a signal to the guage down the third wire in the form of a voltage level (12.0v = Tank Full, 0.0v = Tank Empty) which is then translated by the guage into a fuel level. Is there something wrong with my description?

Mick

Forum Moderator Joined: 18 Feb 2004 Posts: 7432

off topic but fuck me thats shiny! original paint?

Spammer Joined: 27 Jul 2004 Posts: 5717

thats black for you mate ,no surprise .

FCS Event Manager Joined: 04 Jan 2005 Posts: 3680

ahhhhh now i see what u mean by conversion, is that a megane dash in that 19?

from the circuit diagram the white wire on the fuel sender in the tank becomes an orange wire for the gauge connection and the mauve one stays the same.
black wire on the sender of course being the earth.

not sure why you have 4 wires when the diagram only shows 3 wires from the sender unit.

i would say your way of thinking is correct, power down one wire into sender with a variable resister or similar sending back a voltage in respect of how full the tank is.

Affiliate Joined: 28 Jan 2005 Posts: 360

Yep, that is indeed a Megane dash and clockset in a Ph2 19 Cool

We've also got the 2.0 '710 lump with coil pack ignition in there to which is a great improvement over the old 1.8 and should be even better once the cams, management and planed comp-ratio increase has happened. We're hoping to see about 180 horses from her but time will tell on that one.

Digressing - The problem is that the 19 sender has two white wires, a green wire and a black wire. Now i've tried putting 12v down the whites and green and I've had no signal votage in return. I think i'm going to have to dismantle the dash again and get a test meter on the multiplug for the guage to track them back in the loom.

Affiliate Joined: 28 Jan 2005 Posts: 360

Neal 19 16v wrote:

off topic but fuck me thats shiny! original paint?

Yes sir, it's 100% original paint and that's not been cleaned for 2 months since we started the project. It's totaly ditched when you're up close and personal. TBH, it's looked after though and is religously cleaned and constantly waxed all year round. It does need a new sill on the passenger side and as the drivers door is dented we're thinking about getting all the little bits resolved and then fully repainted in the same colour.

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

theres 5 wires poking through the floor to go to the tank.

2 wires are a feed to the fuel pump, the other 3 go to the sender.

Fuel pump has the inertia cut off switch beside the megane under bonnet fuse box.

Fuel pump wiring goes through the dash.

Megane also has the pump and sender in 1 unit so theres only 1 plug for it.

Affiliate Joined: 28 Jan 2005 Posts: 360

Thanks for that Chris - That backs up what i've found in the Megane side of the loom. The problem i'm having is identifying the ajoining wire colours from the 19's sender loom and what they do. I'm pretty sure the Megane is as follows:

Orange - Sender power
White - Level Signal
Brown - Sender Earth

The 19 seems to have the following at the sender under the inspection cover:

White - ?
White - ?
Green - Level Signal?
Black - Earth

NOTE: The two whites join to the same pin in the multi plug!!

Any clues?

Mick

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

right I have gone to the shed and pulled out the 16V rear loom.

4 wires to the sender.

black earth shared with the fuel pump earth.

creamy with black tracer opposite from the sender earth goes to the top right on the brown plug

grey wire beside the last one goes to the 2nd from left 3rd up on brown plug

cream no tracer goes from the p9in next to the earth at the tank to the 1st from left 3rd pin down.

What do the 3 do? not sure, not sure as is I don;t knwo which pin is which feed.

2 to the pump.

White with red tracer is for the pump pos feed. At front near dash its top 2nd from left in the brown plug

Black is earth (on rear panel 10mm bolt)

No pins on the ph1 16V loom join, they are all seperate aside from the earths.

Affiliate Joined: 28 Jan 2005 Posts: 360

Cheers again Chris. I wasn't expecting you to go pull a loom out and test it for me but thanks. I've got the fuel pump working fine but I am thinking that the Ph1 and Ph2 might have subtle diffs in the looms as there is deffo a few pins which share wires and the sender deffo has a green wire with a tracer on it. I do however remember there being two creamy/beige wires on the 19 loom so I might strip the boot again and stick the meter on them regardless to see where they end up.

I've also got to switch the 19's clutch pedal for a Meganes to as the 19 rachet won't allow the clutch arm to engage fully (Short by 10mm) and ends up pulling the cable off

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

I just happened to nearly do my knee in my kneelign on the 16V sender I have spare.

Its only got 2 terminals on it

the earth and the grey wire on mine are all that are used

Affiliate Joined: 28 Jan 2005 Posts: 360

Is it off of a phase 1 or 2 16v?

I only ask as I think the Megane and phase 2 19's use a box of tricks to interprut the signal from the sender in the tank to be read by the guage... or am I talking even more bollox than normal?

Forum Moderator Joined: 02 Mar 2004 Posts: 19978

ph1 of course.

Righty having gone back out and looked at a ph1 carb (gauge) sender it has 3 connections.

So the way it is I beleive is the digi dash on the ph1 just gets the resistance, (usual 2 wires on the sender but 2 are soldered together) whilst ther gauge models works as a POT.

So digi dash version has 2 wires but gauge models need 3 wires.