ZX: drunk fuel gauge

ZXturbo_Aura · Post by **ZXturbo_Aura** » 12 Mar 2004, 02:18

hi all,
my fuel gauge acts constantly drunk, it stays near the full mark for days on end, then suddenly drops, then when it is on the red, with a constant red light,it suddenly decides to tell me i have quarter of a tank left! this happens on flat, straigh, bends, hills, anywhere!so it cant be the fuelleaning towards the sensor when on hill etc?? could it be a bad ground or something?its really annoying because i dont know how much fuel i have! lol!
Dan

Post by **Jon** » 12 Mar 2004, 02:35

Well, its likely the sender unit at fault. Having said that, loads of ZX D's have had this problem. You could swop it for another one (fairly easy job incloving unbolting the rear seat and prising out the LH plastic bung in the floor to gain access).
We had problems with the ZX D/TD years ago when I was at Citroen, sometimes even fitting a new sender did not completely cure the problem, there was a mod whereby you emptied the tank then put in about 5 litres of diesel, then adjusted (read, bend) the sender unit float to put the low fuelling light on at that point. To be honest, it didn't really help, the sender unit is pretty poor. Mine reads a confident 3/4, I overtake some bloke then its 1/2 for a bit then goes back up to 3/4 on the next downhill stretch!!!

ZXturbo_Aura · Post by **ZXturbo_Aura** » 12 Mar 2004, 02:39

i know im being lazy but off the top of your head jon, how much are the sender units?! i was told they were pretty steep?
Dan
thanks!

Post by **Jon** » 12 Mar 2004, 03:06

To you??? Well I have a brand new one in unopened Citroen box in my garage for ZX TD, a tenner to you. If it really matters I suppose I could take a pic of it. Otherwise, about £35 quid plus VAT at your local dealer.

Post by **martyhopkirk** » 12 Mar 2004, 03:43

My ZX fuel guage does this, mind you what with the dodgey central locking (see other thread), wobbily speedo, missing dash lights and general clunky rear end its not really a problem.... (i.e.read im too lazy / skint / mechanicaly inept to be arsed sorting it out)
I know from experience i get 480ish miles on a tank.... just keep an eye on the trip counter... (oh thats tempramental on mine too, sometimes not resetting).
Its all a question of can you live with it?

James.UK · Post by **James.UK** » 12 Mar 2004, 04:41

My guage works fine fortunately, but I carry a gallon plastic can of cooking oil in the boot 'just in case' I run out.. Maybe that's why the guage behaves itself? lol..

Brian Oblivion · Post by **Brian Oblivion** » 12 Mar 2004, 06:03

I think I'll carry one of those fancy purple extra virgin olive oil bottles with rosemary and thyme in on the back parcel shelf!

voyager · Post by **voyager** » 12 Mar 2004, 06:42

My trainining was with Ford, but this is not such a strange problem. Firstly remove and check the sender for any breaks or shorts. It's a good idea to connect a resistance meter to it to check that the resistance varies evenly as you move the float up and down as well.
If all apears OK then re-fit it and check the voltage to see if it's constant at the sender and guage.
On some fords we got this problem and it was usualy a faulty voltage regulator ( located on the back of the instrument cluster on most Fords ) Not sure if ZX has one on dash but check that voltage is constant anyway as an increase involtage will cause the guage to read higher.
Paul.

uhn113x · Post by **uhn113x** » 12 Mar 2004, 13:13

Hi Dan
I assume the fuel gauge is the same as most inasmuch as to make it read full, the sender has to be at minimum resistance. So, it would not be a bad earth - this would make it read empty.
To get an idea of where the problem is, fill up and disconnect the sender, then go for a long drive. It should read empty all the time. If not, you probably have a chafed cable shorting to earth somewhere between the sender and gauge.
My BX, Dyane, DS and GSA all read differently when you face uphill or downhill - that is down to the tank shape and sender location.
The Dyane gauge also bounces round on a bumpy road - I am thinking of damping it with a 1000mfd capacitor across the gauge.
Mike

Post by **RichardW** » 12 Mar 2004, 13:21

Our ZX TD gauge is a bit haywire too - had filled it up and done just under 300 miles, but gauge was showing empty. I was fearing we were only getting 25 mpg, but wife filled it up and got less than 30 litres, so MPG appears OK, gauge is not. It won't be getting sorted though - just rely on the trip meter as I have always done!
You could always buy a multiplexed Xsara, but the gauges on those are not any better - my parents' one is all over the place, despite having had a new sender fitted!

TomH · Post by **TomH** » 12 Mar 2004, 13:38

Mine is a bit odd, but not unpredictable really! Stays at the top for about 60-80 miles then plummets to halfway and goes slowly down from there, staying at the bottom for ages before the light goes on.

Dave Burns · Post by **Dave Burns** » 13 Mar 2004, 14:40

Yep mine too, it was ok untill I parked across a steep slope at an angle one day, after that its now all over the shop, so thanks Citroen for yet another high quality component[:(!]
Dave