Your description is hard to make sense. Are you having trouble with dimming lights and slow cranking? That suggests a charging system problem. The first garage said you needed a new what? It won't start, but you drove it today. How can that be?
I guess the place to start is with the charging system test. The engine should start fine if the battery is charged for an hour at a slow rate. Measure the battery voltage after charging the battery both before the engine is started and when it is running. Measure the voltage again with the engine running when the problem acts up. Use an inexpensive digital voltmeter. Those three readings will help determine where to go next.
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Saturday, February 26th, 2011 AT 2:42 AM