What would help would be an articulate question. Does "lose power" mean a loss of voltage/current, or a loss of engine power (horsepower/torque)?
Battery may have a dead cell and need replacing.
There is abolt on the bottom of the alternator that holds the alternator to the engine. There is another bolt and bracket on the top that adjusts the belt tension. There is a ground wire, power wire from the starter and a wire that connects to the dash light. There are also one or two belts depending on the year and model of the car.
Your alternator has failed, and the battery has drained from running the vehicle without being able to recharge it. Replace the alternator and the battery should be fine.
Frist disconnect negative battery
To change the alternator in your 1986 Chevrolet Celebrity: 1, Remove the battery ground cable. 2. Unplug remove the wiring from the alternator. 3. Loosen the bolts that hold the alternator in place. Remove the drive belt. 4. Remove the bolts and the alternator will pull out. Reverse the process to reinstall the new alternator.
I would check the power right at the starter. Either the solenoid on the starter is defective or the connections/ battery are poor.
Bad ECU, replace.
Loose cables, bad battery, alternator or starter.
Take it to your local auto parts chain store. Most of them will check your battery and alternator for free.
Where is starter relay on a 1986 volvo 240gl
Check the charging system first. With the car running use a multimeter to see output of the alternator at the battery. Should be 13.5 + volts if the battery is not at 100% charge. If the guage is right and the voltage drops off check to be sure you have power to the back of the alternator. It's possible you may have a alternator problem or if it's externally regulated(I think it might be) a voltage regulator problem.
Left side on front of motor. Follow the battery cable and it will lead you right to it.