I broke 2000 miles with the 914 EV this week. The car has been running smoothly with no complaints. One of the "features" of the 914 is that the turn signals come on (but don't flash) if you leave the turn lever in the "left" or "right" position, even when the ignition is turned off. This presents the dilemma of running down the 12V battery while the main pack is charging. If the 12V battery is dead, you need a small 12V battery (9V would probably work) to activate the DC-DC converter relay to bootstrap the 12V charging process.
The PakTrakr with the series 100 ohm noise-reduction resistor has eliminated all the spurious error alerts. I took a serial log of all the batteries during my commute (graph below) and found battery #11 (the second battery in the front compartment) to be drooping slightly more than the others. I noticed that it tended to have more acid around the battery caps on top of the battery and it's fluid level was lower. The accuracy of the PakTrakr is only 0.1V so the voltage droops look like sharp steps on the graph.
UPDATE: Roger asked me to explain the graph above in a little more detail. The PakTrakr logs voltage for each battery and then dumps it out a serial port in .csv (comma separated) format for MS Excel. I captured the above graph from the chart that MS Excel generated. The batteries are 8 volts apiece and the serial port dumps tenths of a volt (scale on the left edge). This graph displays voltage for all 18 batteries (each is a "series) in the system. As I drove to work with acceleration and regeneration, the voltage on the batteries varied. The batteries with reduced health or capacity will tend to droop lower during heavy acceleration and spike higher during regenerative braking due to higher internal resistance or lower energy capacity. As I mentioned earlier, I found that series #11 on the chart was consistently at the lowest value during heavy acceleration periods, so I suspect that battery will have some issues sooner than the others. I topped off its water to increase its storage capacity a bit. You'll also notice that the "steady-state" voltage at the end of the chart is lower than at the beginning, showing that the pack has gone through some discharge during the 15-mile commute.
I'm getting more involved with the OEVA club. If I don't get elected co-chair next Thursday, I'm going to start an open-source EV conversion kit sub-group within the OEVA. I even have a lawyer friend who is willing to assist with some of the open-source gotchas involved in such a project. Researching my motivations and how much I'm willing to throw myself into this will definitely be important.
Have a great weekend everyone.