Living with a car from the present - 2019 Bolt EV

Woohoo! I'd love to see what's actually involved in the swap.

And after all that, it probably feels exactly the same :) Did you get a capacity increase out of the deal? IIRC the newer Bolts are packing a bigger battery.

Keith Tanner said:

Woohoo! I'd love to see what's actually involved in the swap.

And after all that, it probably feels exactly the same :) Did you get a capacity increase out of the deal? IIRC the newer Bolts are packing a bigger battery.

I believe it's not actually bigger (more cells), but imroved chemistry in the cells.

Honestly with the new tires and the weather variability this time of year, it should be difficult to tell. I reset the odometer and energy meter, so I'll report what I see!

I had the weirdest experience with this rental car. Apparently it's powered by a hydrocarbon liquid, it's extremely flammable and dangerous. In the two short days I had this car, the liquid was nearly gone. I was forced to go to an establishment which sold his liquid for an absurdly high price. For some reason the place stank of cigarettes, and had advertisements everywhere for cigarettes and chewing tobacco. I don't understand the correlation between these two demographics. Regardless, I had to get out of this rental car and address this strange kiosk. I had to put in my credit card, and then take out a hose from its position where it could transport this incredibly dangerous liquid from a tank, which I was apparently standing on, to the tank in the back of the rental car. This took a long time, at least 5 minutes, was extremely expensive, and was so dangerous that the car had to be turned off during the event. I'm glad that general motors is covering the cost of this fuel, because it was extremely expensive. I spent the equivalent of 2 weeks of my driving cost in just 2 days with this rental, and it was a rather fuel efficient rental!

:) Man, if we were trying to sell the concept of ICE in an EV world, it would be so hard. They make everything so difficult and they're complicated and they will kill you if you run them in the garage and their very fuel can give you cancer if the fumes don't explode. And you have to keep going to a special place to refuel them all the time, not just when you're away from home.

I meant a bigger battery in terms of capacity, not physical size. That would be a nice bonus upgrade for sure.

This morning was my first real data point. I always charge to 90% so that I have regenerative braking the whole time. Today my range was estimated at 255 even though it was only 44° outside. I don't have an exact back-to-back, since the temperature has fluctuated so much, and since the new tires have changed things a bit, but that's a good 20 miles and change more than I expect. I suppose it's reasonable to attribute that to the new battery.

In reply to tuna55 :

The irony is not lost that you were in the rental with the dangerous liquid  because of a few of these events 

To be fair, the Bolt is on my short list as a potential entry point into the EV market to replace my Fusion. When looking at the use of our two daily drivers over the past 5+ years I couldn't come up with a single scenario where we would ever have charged away from home. 

I have enjoyed following this thread and your experience with the Bolt. 

fusion66 said:

In reply to tuna55 :

The irony is not lost that you were in the rental with the dangerous liquid  because of a few of these events 

To be fair, the Bolt is on my short list as a potential entry point into the EV market to replace my Fusion. When looking at the use of our two daily drivers over the past 5+ years I couldn't come up with a single scenario where we would ever have charged away from home. 

I have enjoyed following this thread and your experience with the Bolt. 

Ha!

I don't have data on ICE fires, but the Bolt fires were something like 8/70,000, so I think I was safe.

In reply to tuna55 :

I have not dug deep into it...but one data source:

With ICE cars, it looks like electrical issues are most often to blame

If you smell gas you have it checked out so you do not catch fire. How do you tell if your battery is going to catch fire?

If you smell electricity :)

Not all fuel leaks give time to check things out. I had a fuel fitting fail when I was on track once. Went from a fully sealed system to a 60 psi AN-6 geyser spraying all over the hot engine bay. Got away with that one but it sure had me moving fast. 

Gasoline is nasty stuff overall. 

Just to recap, the Bolt is rated for 259 miles. Today range was 255 with brand new tires (which I would expect would drop the range) as well as cold temperatures charged to 90%. This means well over 300 miles charged to 100% in warm weather. Wow.

That's sweet!

Does the "recalls due to fire risk" data include the Mazdas that were recalled because of spiders in the gas tank? One of the weirder recalls - and they've had to do it twice.

https://money.cnn.com/2014/04/06/autos/mazda-spiders-recall/index.html

I had my first problem yesterday, and it has be pretty annoyed. Before I type it out, let me remind the reader that the Bolt has all stainless brakes, and uses them only when hill assist is active (maybe a few times per day) and when I hit the pedal during an urgent stop (maybe twice per week at this rate). The rotors look like mirrors and everything was working perfectly. I have 48K miles on the car.

I was driving home yesterday and felt a shudder around 60 mph. It seemed to be speed related, so I slowed down. I flew through the menus and checked all of the tire pressures and found that the passenger front was high, 39 psi. I pulled over and sure enough that wheel was warm and that brake pad was smoking a tiny bit. I let it cool off, turned the traction control off, and drove to the dealer and dropped it off.

I have driven cars with failing brakes. I grew up in the salt belt, and have had my share of sticking GM sliding calipers, and this wasn't that. That results in one pad getting way more wear, often at a severe angle. I've also had my share of ruined rotors shuddering, and this wasn't that. The car tracked straight, even with my hands off the wheel. The caliper still looks like a mirror. I told this to the service advisor, who to his credit was receptive and fun to chat with, and he listened and jotted it all down. He said something like "normally I will not put ideas from the customer on the ticket, but it sounds like you know your car pretty well here". I think the traction control was going bonkers. Now there are some problems with this diagnosis.. There was no traction control light. I do not know if turning the traction control off helped on my drive home, but since the brake was obviously very hot, the dealership was about to close, and locking up a wheel on one of the busiest roads in town during rush hour sounded like a big risk, I just drove slowly comforted mildly by the thought that I might have helped keep the pad and rotor alive a bit longer.

Stay tuned. It's annoying for sure.

No trouble codes were found in the traction control or ABS or wheel speed sensor functions. The rotor was indeed discolored, but only on the inside. The caliper and its piston slid freely when inspected. They surmise that some debris got caught in the caliper. It's an awfully convenient diagnosis but it has merit. Either way, a $90 diagnostic charge and I can pick up the car tomorrow.

Finger crossed. 

Nope. I felt it again yesterday. Turning the traction control on/off didn't change the condition. I also could feel the brake dragging at lights if I put the car in neutral and rolled it back and forth with my body weight.

So is there a failure mode for a caliper that only sticks when it's warm and only sometimes? A caliper is cheap, that is if I can figure out how to bleed it.

There is a failure mode like that if the master cylinder is misadjusted. If the bleed hole is covered when the brakes are not applied, the fluid has nowhere to go when it heats up so it pushes the pistons out and drags the brakes. I've had a car almost lock the wheels with this problem. 

One caliper is a little more difficult, but if you have a pinched or obstructed line to that caliper I could see it happening, maybe. Are you sure it's actually actuating?

Traction control brings a bunch of other possible problems, mostly in the valve body. 

Keith Tanner said:

There is a failure mode like that if the master cylinder is misadjusted. If the bleed hole is covered when the brakes are not applied, the fluid has nowhere to go when it heats up so it pushes the pistons out and drags the brakes. I've had a car almost lock the wheels with this problem. 

One caliper is a little more difficult, but if you have a pinched or obstructed line to that caliper I could see it happening, maybe. Are you sure it's actually actuating?

Traction control brings a bunch of other possible problems, mostly in the valve body. 

I am assuming I can completely disable the traction control with the button, and also assuming no codes on that or ABS means there are no failures with those systems. I definitely felt the brake dragging even rocking from a stop, so either is unlikely anyway.

No lines are pinched or obstructed (per inspection from the dealer), and I had not touched the brakes yet into my journey at that stage, 45 minutes in. I am not familiar with a bleed hole in a master cylinder, though. Tell me more about that.

In reply to tuna55 :

All master cylinders have a bleed hole which is open when the brakes are not applied. Otherwise they would never go off when you remove your foot from the pedal. Too little master cylinder free play, thus not opening the bleed hole, should make all the brakes stay on, not just one. I think internally collapsing flex hose is a far more likely culprit here. I have seen these failures on relatively new hoses which showed absolutely no external damage.  

To add to that - the bleed hole is the connection between the master and the reservoir. It would potentially make all the brakes come on, but I would think that the caliper closest to the master (from a plumbing perspective) would be the first to engage. It's a viscious cycle, the dragging caliper(s) generate more heat, which engages the caliper more which generates more heat...it doesn't just drag a little and stay consistent. But you asked about a failure mode that could drag a caliper :)

Agreed that it's most likely a damaged flex hose, although a problem valve might still manifest itself even with the TC turned off. I don't know if it would be able to detect a valve malfunction, next time I get a chance I'll dig into the GM CAN PIDs to see if there's something in there.

Keith Tanner said:

To add to that - the bleed hole is the connection between the master and the reservoir. It would potentially make all the brakes come on, but I would think that the caliper closest to the master (from a plumbing perspective) would be the first to engage. It's a viscous cycle, the dragging caliper(s) generate more heat, which engages the caliper more which generates more heat...it doesn't just drag a little and stay consistent. But you asked about a failure mode that could drag a caliper :)

Agreed that it's most likely a damaged flex hose, although a problem valve might still manifest itself even with the TC turned off. I don't know if it would be able to detect a valve malfunction, next time I get a chance I'll dig into the GM CAN PIDs to see if there's something in there.

Thanks!

How do I bleed this thing if I were to replace the caliper and/or hose myself?

TurnerX19 said:

In reply to tuna55 :

All master cylinders have a bleed hole which is open when the brakes are not applied. Otherwise they would never go off when you remove your foot from the pedal. Too little master cylinder free play, thus not opening the bleed hole, should make all the brakes stay on, not just one. I think internally collapsing flex hose is a far more likely culprit here. I have seen these failures on relatively new hoses which showed absolutely no external damage.  

Thanks!

This sounds reasonable.

In reply to tuna55 :

Should be totally normal from a bleeding perspective. I've found that if you leave the bleed screw open on the new caliper while installing and let everything drool, it'll self-bleed the majority of air out during install. As long as you don't take forever to connect everything, you won't suck the master dry.

tuna55 said:

TurnerX19 said:

In reply to tuna55 :

All master cylinders have a bleed hole which is open when the brakes are not applied. Otherwise they would never go off when you remove your foot from the pedal. Too little master cylinder free play, thus not opening the bleed hole, should make all the brakes stay on, not just one. I think internally collapsing flex hose is a far more likely culprit here. I have seen these failures on relatively new hoses which showed absolutely no external damage.  

Thanks!

This sounds reasonable.

The brakes will still go off if you don't have a bleed hole - the retraction of the piston in the master still happens. It only comes in to play when the fluid expands/contracts due to heat, which starts to apply the brakes for you. If you have a significant braking event that puts a lot of heat in rapidly, it might feel like the brakes never really release. The bleed hole is also used in the long term to add more fluid into the system due to pad wear, as the total volume of the system goes up as the resting point of the pistons moves out.

GMs seem to have a tendency to fail the flex line in a manner where it acts as a partial check valve that won't allow the caliper to bleed off after brakes are applied.  I've had this happen on three different vehicles that I've owned and also on one of my parents' cars.  On my Silverado, it was an intermittent problem too.