94 Bonneville stalls when gas low, erratic fuel guage
austintx12000
08-29-2007, 07:44 PM
I have a '94 Bonneville which stalls when the fuel is low. Rate of stalling increases as fuel drops below 1/2 tank. Doesn't seem to stall at all when above fuel is above 3/4 full. Sometimes the fuel guage is erratic with wide excursions while driving at steady state, but doesn't seem to coincide with the stalling. It seems to jumping up and down rapidly before stabilizing within a short time (a few seconds).
Fuel pump was replaced within the last year for an unrelated problem which later turned out to really be an ECM issue. The ECM which was also replaced. Is there some sort of pickup attached to the fuel pump which may have come loose and fallen off the new fuel pump preventing gas from being picked up when below a certain level ? Stalling seems to increase when the car is on a slant or going around corners. If I have 1/4 tank and I put the car on a slant, the guage goes to about empty and the problem is easily reproduced, with the enging sputtering for a while first.
If the sender is hosed up and tells the ECM that the fuel is empty, will the ECM turn off the fuel pump ? I read this somewhere, but I also read that once the car is running, the fuel pump is powered by the oil pressure switch, which is consistant with my experience with some other cars.
I wouldn't mind if it only did this at 1/4 tank or lower as I could always just keep the tank above 1/2, but it also happens with higher tank levels, just less frequently.
Fuel pump was replaced within the last year for an unrelated problem which later turned out to really be an ECM issue. The ECM which was also replaced. Is there some sort of pickup attached to the fuel pump which may have come loose and fallen off the new fuel pump preventing gas from being picked up when below a certain level ? Stalling seems to increase when the car is on a slant or going around corners. If I have 1/4 tank and I put the car on a slant, the guage goes to about empty and the problem is easily reproduced, with the enging sputtering for a while first.
If the sender is hosed up and tells the ECM that the fuel is empty, will the ECM turn off the fuel pump ? I read this somewhere, but I also read that once the car is running, the fuel pump is powered by the oil pressure switch, which is consistant with my experience with some other cars.
I wouldn't mind if it only did this at 1/4 tank or lower as I could always just keep the tank above 1/2, but it also happens with higher tank levels, just less frequently.
richtazz
08-30-2007, 03:01 PM
Welcome to AF. Do you have a check engine light on, and if so, what codes are stored? IT sounds like the wiring harness from the car to the fuel level sending unit is not making a good connection or your fuel sender is bad, fairly common issue on 92-97 LeSabres. This would explain both the erratic fuel guage and intermittent starving for fuel.
jpgr87
09-15-2007, 04:25 PM
I had a stalling problem with my bonneville last year, replacing the fuel pump stopped it. It would occasionally stall below a quarter tank, going around sharp turns and such. To be safe, it'd be a good idea to replace the fuel filter too.
The dashboard in the bonneville is notorious for breaking internally and showing erratic signals. My oil pressure gauge does freak out, but that could also be the oil pressure sender unit. Jumping then stabilizing sounds like it could be a loose connection somewhere
The dashboard in the bonneville is notorious for breaking internally and showing erratic signals. My oil pressure gauge does freak out, but that could also be the oil pressure sender unit. Jumping then stabilizing sounds like it could be a loose connection somewhere
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