2001 jetta...1st time I kept it outside overnight in the cold. Went to start it this morning, it started up but then died out after about 1-2 seconds. Tried 5 times, would not continue running. Finally I gave it some gas once it started and it continued to run. Once engine was warmed up it would start and continue running but idled very low and sounded as it was going to die...Any thoughts??