Fuel Gauge Faults When Battery Disconnected

[rwindeknecht]

When the battery cables are disconnected on my 97 Buick Park Avenue, the fuel gauge needle swings all the way to the wrong side of the peg and will not function. My mechanica had to disassemble the dash and somehow reset the gauge needle. Is there any way to prevent this problem?

[gpinchin]

Same car, year, and problem here, good to know it's not an isolated incident. 5 screws, a bunch of snaps, and about 15 minutes seems to get it fixed. I notice reconnecting the -ve battery terminal seems to be the cause with my car. Might be that the intermittent ground as I try to thread the screw into the terminal confuses the panel and makes it flip.

According to my service manual, the only permanent power to the Instrument Panel is through the 10 amp CSTR/SBM fuse in the Instrument Panel Bussed Electrical Center. (I think it's fuse #10.) That fuse appears to be fed by the 60 amp Batt #1 fuse in the Underhood Bussed Electrical Centre. Next time I have to pull the battery, I'll try pulling the Batt #1 (since its easier to reach) fuse smoothly first, and after reconnecting the battery, I'll try putting it back in again smoothly and see if that keeps it from flipping. I may not get to this for a while, though.

[lweich]

Originally Posted by rwindeknecht

When the battery cables are disconnected on my 97 Buick Park Avenue, the fuel gauge needle swings all the way to the wrong side of the peg and will not function. My mechanica had to disassemble the dash and somehow reset the gauge needle. Is there any way to prevent this problem?

You don't need to disassemble. Just get a couple of strong magnets and with the ignition off, pull the needle around to the opposite side of empty.
The problem has something to do with electro magnetic field in the gauge. For some reason many mechanics are not aware of this.

[huynh]

Hi all,
My problem is a bit different. I have not taken the battery cable off for while. When I am driving the fuel gauge handle just swings back and forth between FULL (all the way to the right) and where I think to be the right spot for it. Each time it reachs the FULL position, the digital fuel gauge shows 533 miles to empty. When it goes back to its right position, the digital fuel gauge shows its right distance to empty.
Any idea to help is greatly appreciated. In case you would like to help faster, my email is [email protected].
Thanks in advance.

[Blue Bowtie]

huynh,

There is a good chance that the level sensor is beginning to fail (in the fuel tank).

[huynh]

Thanks a lot, Blue Bowtie!
I will replace the fuel pump.

[Blue Bowtie]

If the pump is operating, you may be able to repair the fuel level sending unit. Before dropping the tank, check the harness connections at/near the tank for clean and tight connections.

[ggriffin]

Originally Posted by lweich

You don't need to disassemble. Just get a couple of strong magnets and with the ignition off, pull the needle around to the opposite side of empty.
The problem has something to do with electro magnetic field in the gauge. For some reason many mechanics are not aware of this.

I'd like to add to this solution. Suffered the same problem with a 2000 Park Avenue after jumping the battery and creating a voltage surge that spun the needle clockwise to the peg. Read on a few other websites that a very powerful (40-50 lbs.) was required. Tried a 20 lb. magnet and got nowhere.
Then, one day fiddling with a little telescopic magnetic pickup tool, I found I could move the needle - by aiming at the base of the needle, not the tip - but not enough to swing the needle around.

Went to Home Depot and bought a package of 8 round, quarter sized magnets (about 3 bucks) that collectivelly couldn't have pulled more than about 3 lbs.. Stacked them, shut off the key, aimed at the base of the needle, and it swung around easily and quickly to the full mark. Removed the magnet, turned on the key, and the gauge went to the proper level.

Aim for the base of the needle, not the tip. Careful not to scratch the plastic.

[buickultra2000]

GGRIFFIN, Thanks!!! I bought the same magnets at Home Depot and I did swing the needle to full. However now the gas gauge is no longer accurate. It stays on full a long time and when it gets back to the half way mark, there are only 6 gallons left. Any thoughts on where the problem lies? Thanks!

[HotZ28]

Welcome to AF, sorry, but this is an old thread. Please notice the date of the last post before posting and read our Guidelines for Posting in Closed or Outdated Threads-PA