2001 Volkswagen Cabrio Q&A

2001 Volkswagen Cabrio Question: wont start Disconnect the battery and it does. new mass air and temp sensor

I replaced air mass, coil, wires, coolant sensor. wont always start. disconnect the battery and it starts and runs fine for a day -
Answer 1
When youre doing that ,you're resetting a sensor ,which 1 is it ..hmmmmmmm.. -
Comment 1
Which one that I haven't changed will cause it not to start? -