Fuel gauge issue after service

AlistairQ · Feb 19th, 2013, 22:21

The XC70 was in the dealer last week for its 4 year service. All was well except they kept me waiting for a bit when I went to pick it up because “we had to do a lot of software updates on it” – this might be relevant to the problem I am about to describe.

Anyhow, a few days later I needed fuel so brimmed the tank, got 65 litres in. When I pulled out of the forecourt I noticed that the fuel gauge was only reading half full. At first I thought that I had made a mistake so I pulled over and checked the receipt and sure enough 65 litres. Carried on driving and the fuel gauge started to slowly creep upwards. By the time I got home 20 minutes or so later, it was reading three quarters full.

Left the car overnight, next morning the gauge was still reading three quarters full when I started the car, drove for about half an hour and by the time I got to work it was reading full!

Now I don’t know what sort of system the car uses to measure how full the tank is, but I would have thought that if it is some sort of float or sender unit and it had got stuck then it would have continued to rise overnight when the car was parked and the gauge would have read full in the morning. Because the gauge only rises slowly to full when the ignition is on it suggests to me that it is potentially an electrical or software issue rather than a mechanical one (i.e. something being ‘stuck’).
Any thoughts? I haven’t reported it to the dealer yet and it takes me about two weeks to use a full tank so I won’t know if the issue reoccurs until I next fill up. I have a feeling it’s something the dealer has done as its too coincidental for something to have just broken the day after it was serviced.
Thanks

tt82 · Feb 20th, 2013, 07:31

Had this on my V40. A wire on the sender unit starts to break and that changes the amount of current it passes which shows the level. You may find that as you get down towards half a tank it starts reading empty.

The fix was either a new unit (many many £'s from Volvo) or fix the wire (I resoldered the connection but it didn't last

).

rnlisg · Feb 22nd, 2013, 10:35

dont leave it too long contacting the stealer,it will only give them a chance to wriggle out of any responsibility.personally i would have turned round and gone straight back with it.
sandy

Feb 19th, 2013, 22:21	#1
AlistairQ New Member Last Online: Feb 19th, 2013 22:55 Join Date: Feb 2012 Location: Nuneaton	Fuel gauge issue after service The XC70 was in the dealer last week for its 4 year service. All was well except they kept me waiting for a bit when I went to pick it up because “we had to do a lot of software updates on it” – this might be relevant to the problem I am about to describe. Anyhow, a few days later I needed fuel so brimmed the tank, got 65 litres in. When I pulled out of the forecourt I noticed that the fuel gauge was only reading half full. At first I thought that I had made a mistake so I pulled over and checked the receipt and sure enough 65 litres. Carried on driving and the fuel gauge started to slowly creep upwards. By the time I got home 20 minutes or so later, it was reading three quarters full. Left the car overnight, next morning the gauge was still reading three quarters full when I started the car, drove for about half an hour and by the time I got to work it was reading full! Now I don’t know what sort of system the car uses to measure how full the tank is, but I would have thought that if it is some sort of float or sender unit and it had got stuck then it would have continued to rise overnight when the car was parked and the gauge would have read full in the morning. Because the gauge only rises slowly to full when the ignition is on it suggests to me that it is potentially an electrical or software issue rather than a mechanical one (i.e. something being ‘stuck’). Any thoughts? I haven’t reported it to the dealer yet and it takes me about two weeks to use a full tank so I won’t know if the issue reoccurs until I next fill up. I have a feeling it’s something the dealer has done as its too coincidental for something to have just broken the day after it was serviced. Thanks

Feb 20th, 2013, 07:31	#2
tt82 Forum Support Team Last Online: Nov 28th, 2022 17:33 Join Date: Jan 2009 Location: Here.... obviously!	Had this on my V40. A wire on the sender unit starts to break and that changes the amount of current it passes which shows the level. You may find that as you get down towards half a tank it starts reading empty. The fix was either a new unit (many many £'s from Volvo) or fix the wire (I resoldered the connection but it didn't last ). __________________ The more people I meet, the more I like my dog! 2009 V70 D5 R-Design - Jeade'en

Feb 22nd, 2013, 10:35	#3
rnlisg Senior Member Last Online: Jun 8th, 2020 15:43 Join Date: Oct 2011 Location: lydd/kent	fuel guage dont leave it too long contacting the stealer,it will only give them a chance to wriggle out of any responsibility.personally i would have turned round and gone straight back with it. sandy

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)