My van is laid up after failing the emissions test three times. It will be out of commission for a while so I am starting the van and running the engine weekly and I also need to keep the battery topped up. Is it safe to recharge the battery without disconnecting the leads or will I fry the ecu? Also, how long before the gas goes bad. Its 4 months old now and the van still starts but I'm very concerned about it. The tank is about half full. I cannot drive the van as the registration has expired and I need the emissions certificate to register it.

David (1987 Wolfsburg, Tempe AZ)