V8 Vantage - Fuel gauge problem

V8 Vantage - Fuel gauge problem

Author
Discussion

l8lue

Original Poster:

35 posts

189 months

Saturday 27th April 2013
quotequote all
The fuel gauge on my 2006 4.3 Vantage has always been slow to register re-fuelling (it could take 10 mins to show "full") but I assumed this was some form of damping to prevent oscillating level indications.

Last week, with half a tank of fuel in the car, the gauge needle dropped progressively over 20 minutes to show "empty" and the fuel computer warned ---- miles.

The next time the car was started, the reading was normal. The time after that "empty". The gauge now shows only about one quarter tank when full and at random drops slowly back to "empty"

I think that there are 3 probable causes
1) Faulty sender unit in fuel tank
2) Faulty gauge
3) An electrical glitch (ie computer problem) - Note the car runs perfectly well with the fuel computer on ---- miles!

Before I attack the wrong part of the car, does anyone have any experience or knowledge of this problem?

Thanks

drofnavi

477 posts

138 months

Saturday 27th April 2013
quotequote all
Check the sender unit leads for corroded terminals or a bad earth, it might be a simple no or low cost fix.

l8lue

Original Poster:

35 posts

189 months

Saturday 27th April 2013
quotequote all
Thanks - I'll have a look tomorrow. I have a pit in the garage so can look from underneath, or is there an easy way in from the top?

divetheworld

2,565 posts

134 months

Saturday 27th April 2013
quotequote all
l8lue said:
Thanks - I'll have a look tomorrow. I have a pit in the garage so can look from underneath, or is there an easy way in from the top?
http://www.puwer.co.uk/uploads/V8%20Vantage%20fuel%20sender.pdf

Edited by divetheworld on Monday 6th May 18:02

adsl3897

32 posts

148 months

Saturday 27th April 2013
quotequote all
I have a similar issue with my fuel gauge. On mine it seems to only happen on half tank or less, it will just randomly drop to 0 reading, then sometimes go back up, or down...just random. Will be interested to hear of the outcome...

divetheworld

2,565 posts

134 months

Saturday 27th April 2013
quotequote all
l8lue said:
Thanks - I'll have a look tomorrow. I have a pit in the garage so can look from underneath, or is there an easy way in from the top?
Under the carpet in the boot.
The sender is under an inspection cover.

l8lue

Original Poster:

35 posts

189 months

Saturday 27th April 2013
quotequote all
Thanks for the advice. It is really helpful.

I will report back, when successful.

l8lue

Original Poster:

35 posts

189 months

Sunday 28th April 2013
quotequote all
Problem! I pulled the car out to sort the tank connections in the sunshine. However when it started, the gauge read correctly (2/3 full). Longish journey, short journeys and all is well.

As the Vantage has cured itself, I cannot investigate the fault, unless it returns. Good news for me, but I suspect it may be temporary.

I will re-post when there is something to report.

Little Donkey

1,544 posts

140 months

Sunday 28th April 2013
quotequote all
I thought I had a similar problem in my V12V when the fuel gauge needle was dropping at about the same rate that the rev counter was rising laugh


drofnavi

477 posts

138 months

Sunday 28th April 2013
quotequote all
It still sounds like a dirty electrical terminal connection.

yeti

10,523 posts

274 months

Monday 29th April 2013
quotequote all
drofnavi said:
It still sounds like a dirty electrical terminal connection.
What he said. If you can find it, give it a clean and re-seat it. Nothing to lose!!

Cerbieherts

1,651 posts

140 months

Monday 29th April 2013
quotequote all
You can check the sender output with a multimeter, across the red/white and black and white wires (next to each other in the four-way plug) It should read 204 ohms with an empty tank and 10 ohms with a completely full tank. They also seem to suffer with integral resistance build-up in that plug, so well worth giving it a spray with some contact cleaner.

Cerbieherts

1,651 posts

140 months

Tuesday 16th July 2013
quotequote all
Underneath the car, clipped to the rear subframe on the passenger side

telum01

987 posts

114 months

Monday 20th October 2014
quotequote all
This just happened to me this past Saturday - pretty terrifying to watch the fuel gauge slide to zero over the course of half an hour while I'm in the middle of nowhere! I'll be checking all my wires and connections whenever I get the time in the next few days... I really hope it's a simple fix and it isn't the sending unit.