Controller Overheating and Vacuum Pump Issues

It's been awhile since I've posted because, well, things are just kinda boring and working well on the Civic-EV. I passed 4,000 EV miles a few weeks ago and things are still moving along.

For those of you who have been keeping track of weather in the NorthWest lately, we had a hot spell at the end of July. One day of that week got up to 107F. I had a bit of a scare coming out of work when I found that the Civic-EV wouldn't start at all. The paint is dark blue (almost black) and the engine compartment was probably up around 115 degrees. After opening the hood and running the fan on the controller for 15 minutes, the car finally started to move forward without faulting.

I made it almost home. Coming off the freeway, I stopped at the stoplight on the exit ramp and the controller faulted and simply refused to go further, despite repeated "reboots" by toggling the ignition key. Fortunately, two wonderful people helped me push the car to a near by parking space across some local light rail tracks (we had to dodge the MAX light rail, yikes!). I let the car sit there until 10pm to cool off. When I came back at 10pm, it started up and I drove home.

Needless to say, I was a bit concerned about this hot weather situation. I contacted Ives, the controller designer at Synkromotive, and told him about the problem. His response: we've had that problem for weeks. All you have to do is turn up your CPU thermal limit from 50C to 85C degrees. Geez, I wish he woulda told me that before the heat wave hit. The car seems to be running just fine now, even on hot days.

Another issue I seem to run into (now that I'm driving a lot more) is that the hysteresis on the pressure switch for the Gast vacuum pump is rather large. This means the vacuum in the system to assist the brakes varies quite a bit. 90% of the time, this is no problem, but the 10% of the time when there is little vacuum in the system, the brakes hardly work at all. I have to pump them a bit to drain more vacuum and get the pump started again. When slowly coming to a stop, this isn't a big deal, but in emergency stop situations, this has been an issue.

To solve this problem, I purchased a $300 vacuum pump from Victor over at Metric Mind that is much quieter than the Gast pump and should have much tigher hysteresis on the levels of vacuum in the system. I haven't installed the pump yet, but I plan to soon.

Other interesting news: I'm resigning as chairperson of the local Oregon Electric Vehicle Association. It's been a good run for the past two years, but I'm tired of running the organization and it's time that someone with better organizational skills to step up.

Ross Peterson just finished his Civic-EV during the past two months based on the open-source Civic-EV kit and he's got the "EV Grin." I was delightfuly surprised to hear that he didn't have many issues building his battery racks based on the open-source plans. His batteries are a slightly different brand than mine, but they are still group 31 size and fit the plans well.

Stay tuned for details on the vacuum pump installation. Otherwise, best wishes on all your projects.