1987 Monte Carlo 4.3 original tank etc.
Fuel gauge was working fine. Filled the tank till it clicked off and since then it only moves between 3/4 and full. To make matters worse when the car is moving the gauge will move up from 3/4 to full all the time. When it is at idle it may drop as low as 3/4 if the tank is not full. Other than an issue in the tank is there anything I can check to troubleshoot this? Are there any common causes for this problem?
Fuel gauge was working fine. Filled the tank till it clicked off and since then it only moves between 3/4 and full. To make matters worse when the car is moving the gauge will move up from 3/4 to full all the time. When it is at idle it may drop as low as 3/4 if the tank is not full. Other than an issue in the tank is there anything I can check to troubleshoot this? Are there any common causes for this problem?