Fuel Gauge Reads Improperly?

[pipedream]

Long time Lurker, first time poster... First off- I love my SVX- I've owned it for about 5 months now and it's been a complete joy. Of course, it has its bugs- but I learn to appreciate those too.

As the title reads, I'm having some issues with my fuel gauge. It always reads correctly on a full tank of gas- if i fill it the, indicator will obediently move to indicate a full tank. However, after about 70 or so miles of driving, the needle will drop to below empty, and then with more driving (30+ miles) will gradually move back up to almost midway again... It tends to repeat this pattern until empty. The Low Fuel light indicator seems to be properly working, as it does NOT come on even though the needle drops to empty- it waits until my tank is actually getting low to report low fuel. I've gotten use to this bug, since I know the tank on my car is 18 gallons, and I just keep a good sense of how much fuel i have through odometer readings etc...

I was just wondering if anyone had any ideas about this or experienced it themselves...

Thanks so much,
Eric

[Earthworm]

First off, welcome to the site.

This topic has been covered before and is relatively common (as a search will tell you).

I've never had this problem as bad as you have but my gauge has shown lower than it should have. I have learned to not trust the level of gas shown on the gauge.

I do believe the problem to be with the sending unit that actually reads the level of gas in the tank.

[ensteele]

Welcome to the site. If the fuel reading bothers you, you can try a new sending unit like David suggested. I would zero the trip odometer when you fill up. Myself, I use it to tell me how many more miles I can go. They are all about the same as far as mileage goes and that tells me more than the gauge.

[pipedream]

Thanks for the replies- Yeah, it's not a huge deal to me, but it does freak the passengers out sometimes that I seem to drive miles and miles on empty .

I do pretty much just used the odometer to gauge how much gas I have- and it does the trick... I was just curious if it was a common thing (the person who sold the car to me did say it was common among svx's..) or if I was getting snowed.

Cheers.

[msvx95]

I haven't researched this thread, but I had this happen to my 90 legacy. I had the same symptoms. One day I popped the hood and looked at the battery, thinking it was an electrical problem.......I noticed ALOT of white acid caked on the positive terminal of the battery. I disconnected and cleaned both terminals really good with a battery cleaning brush and sanded the connectors. Once I put the cables back on, the problem went away and the fuel gage acted normal again.
Maybe try that.

[gsodonis]

The fuel sending unit is essentially a potentiometer with a 'linear' pot operated by the float in place of a rotary dial. What you are describing indicates that there is a 'dead spot' on the pot. The low fuel light activates when the float drops low enough to complete low fuel light circuit - it works completely independently from the gauge. If you can't live with it, your best solution is to replace the sending unit.

This ezact thing happened to my 1995 Honda Accord. The sending unit cost $100 and was located on top of the tank in the trunk. It took 15 minutes to swap. I haven't investigated what it would take to replace the SVX's unit, but I would guess that it is a bit more complicated. Other have had to fix fuel leaks and such and had to expose the tank, so if you do a search on fuel tank or fuel pump, you might find a write up describing some of the steps you have to take.

[94svxred]

I've had this problem on 2 GMC trucks that i've owned in the past ,But not on my SVX. Earl made a good point about setting the trip when you fill-up, but personaly I usually don't let my tank get much below halfway before I fill-up! I hope you this is only a minor Problem with your car!! As you know there are much greater problems then just the fuel gauge! Good Luck!

[SVXMAN2001]

This is a recurring problem for me and i've just learned to live with it. I always keep in mind how many miles i get to a tank, which is roughly 400 miles. If i forget how many miles i have left I know for a fact i get at least 60 miles once i see the yellow light. Haven't run out of gas yet! Knock on wood!!

[pipedream]

Good info- and thanks everyone for the replies- what a great community. I'll definitely be poking around here more.

I do realize it is a minor problem, and im not overly concerned about it- i just thought i would ask- and yes i have searched over the threads in here (now) and see that others have similar issues.

Thanks for all the help!