How about putting a container of Sta-Bil in the gas tank?

http://www.goldeagle.com/brands/stabil/

Bob

On Jan 4, 2014, at 2:08 PM, David M <covrambles@YAHOO.COM> wrote:

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)