I bought a 04 Rio it had broken timing belt I bought it from a mechanic shop. They rebuilt head and block told me head had blown gasket. After tearing it down discovered it had cracks in 2 cylinder walls. Got a good block and put it back together now it will start run smooth for 5 to 10 seconds then dies. I can't keep it running long enough to turn on mil light.can someone point me in the right direction. Also it was doing this before I rebuilt engine.