Stabilitrak seems over-sensitive? Any way to disable?

[buickanddeere]

Vehicles have stopped a lot of times without ABS. There would still be two channel ABS instead of four channel ABS.
It would be simple enough to use single pole double throw relay contacts. Wire the relay coil to a WOT switch. The front wheel speed transducers would supply their signal to the rear wheel inputs to the VCM when the throttle is floored. Normal ABS etc when not at WOT.

I'm starting to get the feeling that you're making this all up. I HAVE driven the Spark EV without proper functioning ABS and stability control, and I can tell you it's not pretty! The braking system is highly integrated with the powertrain control, so much so that if there is a fault code the system goes into a reduced propulsion power mode (75 kW from battery instead of 120 kW). I suspect that the "vehicles have stopped a lot of times without ABS" comment you're making doesn't apply to EVs with blended braking systems.


Furthermore, the SPDT relay switching during theory would result in an open circuit (momentarily) and erratic speed measurements, which also throws codes and results in lots of horribe consequences related to driving dynamics.

Bryce

Not a problem to set up make before break relaying if a few milliseconds of dropped signal on two of four channels causes problems. There is probably enough lag built into the system to allow for driving on washboard roads to not throw a code.
The VCM isn't going to detect a problem with the front and rear drivers side tires reading the same ground speed. Same goes for the passenger side. There is also some deadband built into that circuit . To not throw a code if the front tire is 40psi and the rear down to 20 and have different rolling radius front vs rear.
Remember this paralleling the front wheel sensor into the rear wheel circuit is ONLY during WOT. On the trip for groceries and to play bingo. The VCM receives all normal inputs.

 

[Electricbowtie]

So I had 2 Firestone Firehawk GT tires (non-LRR) on the front and left the OEM tire on the back since they don't look worn much at all. It looked like the range isn't affected much around town but will find out later when we take longer drives. The grip with the new tires are MUCH better and don't notice the tire spin during the starts.

 

[nozferatu]

So I had 2 Firestone Firehawk GT tires (non-LRR) on the front and left the OEM tire on the back since they don't look worn much at all. It looked like the range isn't affected much around town but will find out later when we take longer drives. The grip with the new tires are MUCH better and don't notice the tire spin during the starts.

Think it's any quicker?

 

[Electricbowtie]

Think it's any quicker?

I guess if you consider more traction equals quicker acceleration, then yes, but really just nice to not have wheel spin everywhere.

 

[nj1266]

The cheapest way to improve the handling on a FWD car is to play with the tire pressure. IIRC, lower pressure in the rear and higher pressure in the front makes the car rotate better.

The next best way is to remove the silly staggered set-up. This is not an S2000 for God's sake. I was told that there is no room to go with 195 wide tires up front. So the next best thing is to go with 185 wide tires in the rear. That will make the car rotate better since there is a lower contact patch.

Finally, stiffer springs in the rear will also help the car rotate better, but I doubt there are any springs made by the aftermarket for the Spark EV.

I do not know if any of these measures will have an impact on the traction control system since I have not tried any of them. But these are the things that I used to try when racing my old car.

 

[Nashco]

The cheapest way to improve the handling on a FWD car is to play with the tire pressure. IIRC, lower pressure in the rear and higher pressure in the front makes the car rotate better.

The next best way is to remove the silly staggered set-up. This is not an S2000 for God's sake. I was told that there is no room to go with 195 wide tires up front. So the next best thing is to go with 185 wide tires in the rear. That will make the car rotate better since there is a lower contact patch.

Finally, stiffer springs in the rear will also help the car rotate better, but I doubt there are any springs made by the aftermarket for the Spark EV.

I do not know if any of these measures will have an impact on the traction control system since I have not tried any of them. But these are the things that I used to try when racing my old car.

Sounds like you haven't actually tried to drive the Spark EV with some gusto yet. Do it. The problem isn't that it understeers so bad you can't drive it, the problem is that if you set it up so it doesn't understeer, that it detects the rotation and takes control away from you to stabilize the car. Fiddle with the tire pressures and sizes all you want, the car is seriously hampered by the stability control. You can NOT disable it, it automatically turns itself back on once you're above parking lot speeds. I'm running a square setup (same tires front and rear), aftermarket suspension, etc. and the car is still an absolute bear to get to rotate without subsequently taking power away from you until the car is stable again. I'm trying to improve my driving style, as I've never raced FWD and I'm also learning how to "drive around" the stability control, but that will only go so far.

Bryce

 

[buickanddeere]

The cheapest way to improve the handling on a FWD car is to play with the tire pressure. IIRC, lower pressure in the rear and higher pressure in the front makes the car rotate better.

The next best way is to remove the silly staggered set-up. This is not an S2000 for God's sake. I was told that there is no room to go with 195 wide tires up front. So the next best thing is to go with 185 wide tires in the rear. That will make the car rotate better since there is a lower contact patch.

Finally, stiffer springs in the rear will also help the car rotate better, but I doubt there are any springs made by the aftermarket for the Spark EV.

I do not know if any of these measures will have an impact on the traction control system since I have not tried any of them. But these are the things that I used to try when racing my old car.

Sounds like you haven't actually tried to drive the Spark EV with some gusto yet. Do it. The problem isn't that it understeers so bad you can't drive it, the problem is that if you set it up so it doesn't understeer, that it detects the rotation and takes control away from you to stabilize the car. Fiddle with the tire pressures and sizes all you want, the car is seriously hampered by the stability control. You can NOT disable it, it automatically turns itself back on once you're above parking lot speeds. I'm running a square setup (same tires front and rear), aftermarket suspension, etc. and the car is still an absolute bear to get to rotate without subsequently taking power away from you until the car is stable again. I'm trying to improve my driving style, as I've never raced FWD and I'm also learning how to "drive around" the stability control, but that will only go so far.

Bryce

Rotate ? Rotate what ? I've enjoyed throtle induced over steer with RWD vehicles for years . How do you "rotate" a FWD vehicle?

 

[Nashco]

Rotate ? Rotate what ? I've enjoyed throtle induced over steer with RWD vehicles for years . How do you "rotate" a FWD vehicle?

http://farnorthracing.com/autocross_secrets10.html

Corner entry oversteer is what this car needs to be faster in competition/spirited driving.

Bryce

 

[markusg]

Got a pair of Avid Ascends myself today. Seems much improved so far. Thanks for the recommendation.

 

[SanDiego]

Markusg:

Got a pair of Avid Ascends myself today. Seems much improved so far. Thanks for the recommendation.

Congratulations on installing the Avid Ascends. We now have 7,000 miles on the ones we installed on the front.
Every time I throw the Spark around a tight corner or freeway ramp, I smile and thank them.
(They show almost no sign of wear, whereas the original Ecopias were in their final stage of life with 9,000 miles on them.)

 

[Oberon]

Congratulations on installing the Avid Ascends. We now have 7,000 miles on the ones we installed on the front. Every time I throw the Spark around a tight corner or freeway ramp, I smile and thank them.

I'm due for the first rotation, so instead of that, I'll replace the fronts with the Avid Ascends. Can you please post the exact model name and number as there seem to be a couple of flavors of Ascend that could fit. Thanks!

 

[SanDiego]

I'm due for the first rotation, so instead of that, I'll replace the fronts with the Avid Ascends. Can you please post the exact model name and number as there seem to be a couple of flavors of Ascend that could fit. Thanks!

The tires we installed are "Yokohama Avid Ascend 185/55R15 82V" (V is the speed rating = 149 mph).

Base cost was $109 each from Discount Tire. I had to special-order them through the local store, and they wanted payment when I ordered them.

 

[beez]

Bump!

HI! So, I have a 2015 spark EV, and the stock front tires are BALD at 25,000 miles.
I gather I might be a record holder for getting this far with them.

Having read a lot of threads on this fine site, I decided to do some experimentation.
I pulled the left front wheel,and unscrewed the mounting screw for the ABS sensor.
I tied it back, replaced the wheel, and went for a drive. Well, this was a mistake.

It reduced propulsion power, and threw a bunch of codes. Now that I've reinstalled the sensor, the codes remain.
I have "reduced power" plus no regen, and no cruise control.

I was going to wire the rear sensors to the front, but now there's no point until I figure out how to read out and reset the codes.
I'm due in the tire store tomorrow for a new set of 195-50 s-drive on the front, but I was hoping to burn these stockers ( they deserve it ) a little before that.

Any advice? Can I reset the code(s) or do I need to take it to the stealer? I was hoping to get a bluetooth ODB/CAN dongle anyway, might be time to pull that trigger and display interesting stuff on my iPad.

Thanks!
Chris

 

[JeremyW]

Try this: With the car off pull the negative off the 12v for a few minutes.

 

[67goat]

Bump!

HI! So, I have a 2015 spark EV, and the stock front tires are BALD at 25,000 miles.
I gather I might be a record holder for getting this far with them.

I don't know about that, I'm over 25k and have quite a bit of tire left until the tread wear bars.

 

[beez]

Follow up: on my second drive after the test, the car returned all functions to normal, except the yellow car with exclamation point icon was still illuminated. On the third drive that went away too. So all is back to normal. I assume there may still be stored codes. I got exactly 25000 miles from the stock tires. I'm not an autocrosser but I do enjoy some sporty driving from time to time. This car is way too fun not to flog. :mrgreen:

Today I got new front tires, Yokohama s drive 195 50 15. They transform the car! Can use instantaneous full pedal from stock with no chirping, no torque steer (smooth pavement) , and no electronic nanny intervention!

I still have the stockers with tons of tread on the back. Please don't tell me some hogwash about how I'm going to die from oversteer. :lol:

I'm still looking for a wireless odb-can dongle and software. Recommendations?

Peace!
Chris

 

[NORTON]

...
Today I got new front tires, Yokohama s drive 195 50 15. They transform the car! ..., and no electronic nanny intervention!

I still have the stockers with tons of tread on the back. Please don't tell me some hogwash about how I'm going to die from oversteer. :lol:

....

I agree! I believe you can mix and match tires on this car and be fine.
Only I think it is Because the 'nanny' Stab Control is saving your bacon if you do start to get sideways,,, and you don't even know it. :!:

 

[beez]

That could be true. With the rears still on, the stab control still gets active in strange situations.
It's really weird, sometimes i'm pulling about 0.01g lateral and it starts pumping a brake...

Other times I can be attempting to slide it around an on ramp and it does nothing.
Even the same ramp at different speeds, it usually is most obvious for intervening when there's truly nothing happening.

Korean software? :ugeek:

 

[Nashco]

The software for the stability control and braking system was developed in the US. That has nothing to do with this, but just FYI.

TLDR: There should be a way to disable the ESC because a human is better than a machine at detecting what is going on with the ****** rear suspension on the Spark EV. Unfortunately, there isn't.

The "inconsistency" you're perceiving is actually just because you're not perceiving all of the tiny details. The stability control is most invasive when one of the rear wheels lifts and any braking (at all) is applied. With the beam rear axle and relatively soft springs, it's quite easy to lift the inside rear tire during cornering, especially if there is any uneven pavement. That's normal behavior for a beam rear axle. Also, if any braking at all is applied while the wheel is up or extremely lightly loaded, then the wheel will stop. My hypothesis is that this extreme deceleration of the wheel is seen as safety-relevant, because the car doesn't know if that is caused by a lifted axle or by an icy patch or gravel in the road. As a result, the car cuts power, puts the stability control into effect to help keep the car on course, and nannies are in full effect.

The result is that some corners that seem minor might cause the ESC to go off if you have a small dip in the road. If the road is smooth or you're at a low speed, the system will seem much less invasive.

Bryce

 

[Anonymous]

The software for the stability control and braking system was developed in the US. That has nothing to do with this, but just FYI.

TLDR: There should be a way to disable the ESC because a human is better than a machine at detecting what is going on with the ****** rear suspension on the Spark EV. Unfortunately, there isn't.

The "inconsistency" you're perceiving is actually just because you're not perceiving all of the tiny details. The stability control is most invasive when one of the rear wheels lifts and any braking (at all) is applied. With the beam rear axle and relatively soft springs, it's quite easy to lift the inside rear tire during cornering, especially if there is any uneven pavement. That's normal behavior for a beam rear axle. Also, if any braking at all is applied while the wheel is up or extremely lightly loaded, then the wheel will stop. My hypothesis is that this extreme deceleration of the wheel is seen as safety-relevant, because the car doesn't know if that is caused by a lifted axle or by an icy patch or gravel in the road. As a result, the car cuts power, puts the stability control into effect to help keep the car on course, and nannies are in full effect.

The result is that some corners that seem minor might cause the ESC to go off if you have a small dip in the road. If the road is smooth or you're at a low speed, the system will seem much less invasive.

Bryce

To all you thinkers and tinkerers out there: would driving the signal for the rear wheel speed sensor with the front wheel speed sensor adequately fake out the Stabilitrack? What would you lose in the process? ABS?