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Q: Engine Control Unit on 1994 Buick Century

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My grandparents have the 1994 Buick Century and recently after a day of sitting in the garage it will not start. It is not the battery I had it tested, when you turn the key you hear a few clicks from a GM ABS relay which is I belive the blow motor relay and then nothing happens. I think it is either the starter or some relay, however could it be the Engine Control Unit???
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it could be your starter motor. The clicks could also be the solenoid on the Starter. have a good Starting and Charging System inspection. Good Luck!
You might want to measure the voltage across your battery terminals as well. A good battery will measure around 12 to 13.5 volts. If you find that the voltage is going down after sitting for a day you may have an electrical drain somewhere in the vehicle. You can put a battery charger on the battery and start pulling fuses in the fuse box while watching the current meter on the charger. If you see the current meter suddenly indicate less current flow as you pull a fuse out, the drain is coming from that circuit that the fuse protects.

Another thing it could be is the alternator. The Buick Century has "idiot lights" on the dash and the light for the alternator should come on briefly at startup and go off if the alternator is putting out proper voltage. However, it could also be that the alternator is putting out proper voltage, but not enough current (the idiot light only looks at voltage, it doesn't care about current, so if there's approx. 12 volts being detected the light will go off). This could be due to a shorted winding in the alternator that's grounding to the alternator case and causing low current output or perhaps bad or stuck alternator brushes. I had to replace my alternator because of low current output when my car would not start after sitting for about 48 hours. The check engine and ABS lights would come on randomly and the coolant temperature gauge would register low temps because of improper voltage/current getting to the sensors. The current was being drawn from the battery because of an internal short to ground inside the alternator.
ANSWER by Thomasdolby456,
October 20, 2016
I've got a 93 Century, 3.3, with 72,456 on the clock. I'm retrieving a 22 (low voltage to TPS) and 44 (lean exhaust) from ECM. Last 2 months I've been dealing with intermittent stalling, but now the car won't start. It used to restart upon cooling off. I've changed the ICM, ignition wires, bad coil, new plugs, new PCV, CKP sensor, fuel filter, battery. I'm ready to junk it, it could be the TPS or ECM. But it's a crapshoot. I doubt it's blown gasket, no leaks detected, oil cap and radiator cap look ok. Can it really be the TPS or ECM ?


You might want to measure the voltage across your battery terminals as well. A good battery will measure around 12 to 13.5 volts. If you find that the voltage is going down after sitting for a day you may have an electrical drain somewhere in the vehicle. You can put a battery charger on the battery and start pulling fuses in the fuse box while watching the current meter on the charger. If you see the current meter suddenly indicate less current flow as you pull a fuse out, the drain is coming from that circuit that the fuse protects.

Another thing it could be is the alternator. The Buick Century has "idiot lights" on the dash and the light for the alternator should come on briefly at startup and go off if the alternator is putting out proper voltage. However, it could also be that the alternator is putting out proper voltage, but not enough current (the idiot light only looks at voltage, it doesn't care about current, so if there's approx. 12 volts being detected the light will go off). This could be due to a shorted winding in the alternator that's grounding to the alternator case and causing low current output or perhaps bad or stuck alternator brushes. I had to replace my alternator because of low current output when my car would not start after sitting for about 48 hours. The check engine and ABS lights would come on randomly and the coolant temperature gauge would register low temps because of improper voltage/current getting to the sensors. The current was being drawn from the battery because of an internal short to ground inside the alternator.
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