My '06 Freestar is losing power on acceleration. The RPMs drop to zero, the battery light comes on, and the red security system light on the dashboard lights up for a few seconds (usually only flashes when van is off). As soon as I release the gas pedal the power comes back. This tends to happen a lot around 75-80 km/h when the van is shifting gears (but not always at this speed). The sound is like a backfire On a few occassions the van wouldn't start in the driveway (would turn over) and then started again later on.