The fuel gauge in my '71 LeSabre works fine, as long as the car is stationary (real useful, huh?) Driving, the needle will stay steady, then start whipping back and forth, then stay steady, then start zinging around again. If I could make it do it on command it would almost be funny, it's moving so fast you can hardly see it. Seems to relate to going over bumps and dips, but not always. I've swapped out the dash unit with a known good one, checked all the connections I can get to without dropping the tank, everything checks out. Sending Unit? Are they repairable, or are there replacement parts available for less then my left arm? Please tell me I don't have to drop the tank - the tow hitch goes under it, and is welded to the frame :af: James
Welded?:jd: Mine does the same thing...if the tank is dangerously low. I guess it's a good way for it to tell me it's almost out of gas:grin: Did you check the ground wire near the tank?
Bad ground. Sounds like rust has compromised the ground, try putting an alternate ground wire from the sending unit to the frame.
You told me not to tell you but....... Check the ground on the sending unit . It may be the Monster ! Good luck ! :laugh: :TU:
Yup, the crossbars are welded to the frame...damned solid, but NOT what I told the shop to do back in '87!!!:blast: The only time it doesn't freak out is when the tank is full, opposite of yours, Smartin. The ground wire connection to the frame is good (great, since I cleaned it and added elec grease). Of course, I haven't gotten to the other end (sending unit end) of the ground. Yet..... Dudes! You're supposed to tell me it's ANYTHING but the sending unit, like maybe "the ashtray lightbulb did it"! I don' wanna drop the tank!!!:ball: James
Ok... It's definately the ash tray bulb causing your problems. If that doesn't fix it, there might be a slight chance it's the ground at the sending unit. :gt::laugh:
Alright!!! An answer I really like!!! :grin: I'll take that durned light bulb out and give it a good scolding this weekend. :spank: (then get out the hacksaw and start the long tedious process of slicing through 4 each 3" x 1/4" steel towbar supports. :ball: ) Of course, a full cooler of medicinal Shiner Bock will make things go much better. :beer Anybody want to work on their biceps? I'm buying... :beer :beer :beer James
My fuel gauge began doing this recently after being out of the car while I had JW replate my bezel. Is there a ground on the dash that affects the fuel gauge? I've tried to check the various connections to the gauge and wiring harness, they seem ok. Also, about 5 years ago I made the mistake of trying to siphon gas out of this car and ended up getting the hose stuck in the neck. After some careful tugging and pulling it finally came out. Any chance I may have damaged a baffel or something on the sending unit that would cause this? It does show the fuel level, but moves around a lot like the fuel is sloshing around. This really bugs me, so if you guys can think of anything else I'd love to hear it. I don't want to drop my tank either.:spank: I'll be checking grounds under the car ASAP.:TU:
My can of Moto-Vation ran out, so I haven't dug into my tank yet, but I can tell you where the instrument ground points are, at least on a Full-Sized Buick, not sure about the Skylark. There's a ground at the sending unit, another at the taillights, and one at the instrument cluster, on the right side towards the top, it's easier to pull the dash pad than try and fit your hand and wrench in from the bottom. The Fuel gauges are dampened, meaning that there are two coils opposing each other for control of the needle, which is supposed to make it move slowly, unless you/we have a spastic ground. First thing I'd do is check to make sure the gauge is fully seated in the instrument cluster. Mine push in / pull out, no screws holding it in. Then get a multimeter and confirm continuity to ground, but I forget which terminal it is (there are 3). Clean up the grounds, swap out for a known good gauge, and if that ain't it, you get to join the "tank-droppers" club. On full-sized cars, the sending unit is enclosed, looks kinda like a big beer can, don't think you could hurt one with a hose, unless you really went to town. You might ask in the "Sparky" forum if anybody can tell you which lead is the gauge ground. Good Hunting! James
Check for a ground wire coming out of the harness at the taillights and attaching to the frame as well as the ones coming to and from the sending unit on the tank. One person wiggles the wires while the other watches the gauge.
Thanks for the info James and Jim. This sounds a little different from my dash, but you've told me enough to get me headed in the right direction. I think with the help of my assembly manual I can find all the grounds. Good to hear it's probably not in the tank. Thanks again.:beer
Oh, Dang! I forgot that wobbly fuel gauges are always caused by the ashtray light going astray. :grin: Just take the bulb out, turn it 180*, and reinstall. Should have everything back to normal. :laugh: If not, a quart of medicinal Bourbon should make it better. James :spank:
