Blame the potholes

Before you read the following post, you should know that I drive this car daily.
It may seem that this blog recently is nothing more than a list of  problems, but when the car works (which it does 99.9% of the time) there is nothing of any interest to post - "disconnected charge cable, backed out of garage, drove to work, drive home from work, connect charger cable..."

Yesterday I had a little trouble getting to work. Along the way my controller appeared to shut down - the Charge light went out and the Check Engine light went on plus, I had no power. I coasted to a stop and restarted the car. Everything worked fine. I took the streets to work in case it decided to fail on me again and once I parked at work, I hooked up my laptop to my Zilla to read the error codes. There were 3 of them - the 12v supply was too low, the contactor opened unexpectedly, the motor RPM was too high. Sounded pretty serious, but I remembered a similar set of errors when my 12v SLI battery failed and I had left the door ajar one night, leaving the interior lights lit for 14 hours... I decided the SLI battery was to blame and after work, took the streets home without incident. Once back home, I hooked up my 12v charger to my SLI battery. It showed it was at 100% - but I ran it through a charging cycle anyway.

Next day, I drive to work without incident. Ont the way home, however, it stalled, First on the freeway (i was able to coast down the next exit where I was able to restart it), then at a left turn (sorry to the people behind me) then at a traffic light (more sorries to those behind me).

I figured it must be a loose 12v wire. Saturday I popped the hood and poked around for a loose wire. Everything looked fine...until I noticed the ground connection under the relay box was loose. I tightened it up and took her for a test drive - all good. A simple fix to what sounded like a serious problem.

The potholes must have rattled it loose.

Electric Toyota Miata?

Over the weekend I was checking the throttle and noticed that it didn't go "full on" when the accelerator was fully depressed - it only made it 90% of the way. This meant I wasn't getting 100% of the power even with the pedal to the metal...

I reworked the cable connection to the throttle using a cable stop from Kragen and moved it to a lower hole on the actuator arm. This made the car much more responsive - less cable travel to get the same amount (or more!) speed.

Monday's commute was a little more fun than normal. First it was more responsive, so I was passing cars, making abrupt lane changes and generally enjoying the ride.

On the way home I floored it and felt the cable jerk - I released the pedal, but the car decided she was a Toyota and was at full speed  - the throttle was stuck. I pulled up on the accelerator with my toe, but that did nothing, so I switched off the ignition, then put the key back to the first position (accessory) so that the wheel wouldn't lock up on me, and coasted to a stop on the shoulder.

Under the hood I quickly saw that the cable stop was stuck against one of the housing screws on the potbox. I bent the arm a little toward the front of the car so that there was clearance again.  Checked it once or twice, then hopped back in and waited for a break in traffic. I accelerated a little slower so as not to tempt fate, and drove home. After a couple more tests in the garage I was convinced that all was okay.

So, I think this illustrates one of the advantages of building your own car - or at least working on it - you know what all the parts do and can quickly remedy a situation that would have stranded an average motorist.

I guess that's one way to look at it...

Bad SLI battery

Well, on my way to work Wednesday morning the check engine light came on solid. This is the Zilla’s way of telling me that something is amiss. The can continued to drive with full power and the Zilla wasn’t overheating (according to the gauge) so I continued my drive. Once in the parking garage I plugged in my laptop and looked at the error codes. I was surprised to see a whole bunch of 'em:

1224 - SLI battery too low and caused shutdown of controller
1221 - Major Overspeed Either Motor Beyond redline by X
1223 - SLI battery below warning threshold
1124 - Main Contactor Stuck On

2 of these, the overspeed and contactor stuck on are pretty serious, but the motor wasn’t over-reved, and the contactor was not stuck on…

By the way, SLI stands for Starter, Lights, Ignition since that's the role the battery plays in a gas car. In an EV, it's more of a buffer to keep the 12v system running during heavy loads.

I cleared the errors and thought I’d take a look at it again on the way home.

After work I drive the car out of the garage without the check engine light lit. On my way home the light came on steady again. It was raining so I was using my wipers and headlights, so then I started to think the real error was low SLI battery voltage and this low voltage was causing the Zilla problems in its logic which made it think the motor was over revving or the contactor was stuck.

A few blocks from my house it did stall, but I was able to get it running again and brought her home.

I tested the voltage on the SLI battery – 12.4v, not too good. I got out my 12v charger and charged it up.

The next day I drove it to work when the check engine light came on again. Once in the garage I checked the error codes and this time it was just 1223 - SLI battery below warning threshold. I left work a little earlier to avoid using the headlights, and it wasn’t raining, so the trip home was, other than the check engine light staying lit, uneventful.

Back at the house the SLI battery again showed 12.4v. I put it on the charger for a couple of hours, but when I removed the charger the voltage started to drop. In an hour it was back at 12.4v - must be a bad battery.

I checked on line and the nearest auto parts store, Kragen, doesn’t carry them. I tried Sears, and they don’t carry them either. I was thinking I was going to have to order one on line and pay a hefty shipping fee, when I found that Auto Zone did carry them and the one 20 minutes away had one in stock!

Saturday I pulled the old battery, picked up the new one and gave them the old one in return. Connected it up and thought I was all set…

Monday on the way home the light comes on again! Same error, 1223. I put the new battery on the charger and checked under the hood to see if my Iota was disconnected. It was wired fine, but I did find one of its fuses blown. Not sure when this would have happened (maybe when installing the new battery?), but this must be why the new battery died on me. Just the same, the old battery was bad because it wouldn't hold a charge.

So, moral of the story?
- Low SLI battery will make your Zilla think strange thoughts
- Check your fuses!

ZEV Stickers

I just got a letter from the DMV in Sacramento with 3 silver stickers. These are similar to the yellow stickers you see on hybrids in CA, but these are better - they're silver.
These will let me drive in a carpool lane and park in an "EV only" spot for charging.

Earlier, the DMV denied my application because they were not aware the car was converted to electric. I sent them a response with the BARs report showing that the state representative attested to it being fully electric.
How could they say no...

Range update

So, I probably have a good 10 months of driving on the car and the battery pack is broken in quite well. The SOC gauge has been showing over 100% in the morning for a few months, but now it seems pegged. I was estimating the old fully charged SOC at 110% but now I'd say it's 120%. After I drive the 4.5 miles to work and she sits a few hours it shows 100% SOC. When I return home and let her sit, it now shows 70% remaining. These are highway miles too, at 60+ MPH...
Back in June I did a test and put 17 highway miles on a full charge. Now I could probably do 20 or 25. Maybe I should revise the range up a bit?

New plate

My wife was driving the car one afternoon and got a ticket for no front license plate. Since the car didn't come with a front plate, I needed to get a new set to clear the ticket. Sounds like a good excuse to order personalized plates... Took a few weeks, but I picked them up on Tuesday. Now I just have to get the front plate installed...