Chevy Bolt EV Forum banner

61 - 75 of 75 Posts

·
Registered
Joined
·
6 Posts
It's almost like the vehicle doesn't artificially center the steering correctly. When it pulls it literally feels like the vehicle thinks pulling right is straight. It's hard to describe, but it definitely doesn't feel like a typical misalignment. My frustration is that GM doesn't really have an answer.
 

·
Registered
Joined
·
5 Posts
I agree. I do know the road does affect it... It will pull harder to the right depending conditions crown or ruts.
 

·
Registered
Joined
·
549 Posts
I've found this thread interesting from the start. It's most odd that Chevy can't find the problem because it obviously isn't a design issue since not all Bolts of the same year/trim have it. I wanted to mention that I think we have different degrees of this complaint and all are being lumped here. That's probably a good thing but it might be good to distinguish them. That is, when I first got my 2019 Premier, I noticed it pulled to the right a bit so I found this thread. After driving the car a couple thousand miles, I found two things: first, the pull greatly reduced after the tires wore in and second, on my particular car, it isn't so much a pull but a follow: my car follows the crown. It'll actually track perfectly straight on a level road or track left if the road crowns to the left versus the right. I attribute this to the alignment spec of the Bolt and I suspect it is aligned for hyper miling which makes it a little more "loose".

But I've noticed that there are also people reporting a hard pull and lack of the steering wheel returning anywhere near center, neither of which affects my car. I wonder if these two complaints are overlapping, mutually exclusive, or what? It is my uneducated guess that there are two things that cause this same general complaint. One can be perceived as a "light" pull to the right which, after further investigation, can be found to be the car just following the crown which happens to almost always be to the right: it can be hard to find a road that crowns left but sometimes the left lane on a multi-lane road will. The other seems to be some mechanical problem with the steering, steering gear, or electric power assist.

I guess my point is: when posting, it might be good to always list the degree to which this is happening and whether or not you've tried to find a lane that crowns left to see if the car pulls left on left crowns and right on right crowns... and whether or not your steering wheel resists self-centering.

Mike
 

·
Registered
Joined
·
59 Posts
Discussion Starter #65
Following up on this issue. My Chevy dealer hired a new service manager who worked with me. Finally got Chevy to perform a "Clear Active Pull Compensation Learned Limits" function with the scan tool. At first Chevy corp balked and would not allow them, or perhaps pay them for the service. Our Bolt steering wheel has been level since and tracks straight.
 

·
Registered
Joined
·
2,611 Posts
Following up on this issue. My Chevy dealer hired a new service manager who worked with me. Finally got Chevy to perform a "Clear Active Pull Compensation Learned Limits" function with the scan tool. At first Chevy corp balked and would not allow them, or perhaps pay them for the service. Our Bolt steering wheel has been level since and tracks straight.
Is it just me, or does this seem to indicate that the LKA system was forcing the Bolt to track to the right, even when LKA was turned off?
 

·
Registered
Joined
·
6 Posts
I’m interested to see if this would fix my very similar issue. It seems like such a simple thing to think of for them not to do. After 5 alignments you would think they would consider it as a possibility.
 

·
Registered
Joined
·
181 Posts
Interesting read here. My new 20 Bolt just seems to "hunt" too much regardless of road type. I chalked it up to non LRR tires but maybe there is more too it.
 

·
Registered
Joined
·
24 Posts
Finally got Chevy to perform a "Clear Active Pull Compensation Learned Limits" function with the scan tool. At first Chevy corp balked and would not allow them, or perhaps pay them for the service. Our Bolt steering wheel has been level since and tracks straight.
Can you describe more what "Clear Active Pull Compensation Learned Limits" is? Sound interesting as my pulling is still unresolved after multiple wheel alignments (that were never out in the first place) and also after replacing the entire steering rack. Is this something that the dealer can override in the computer and make the system apply more force in returning the steering wheel to center or something?
Thanks
 

·
Registered
Joined
·
2,611 Posts
*It doesn’t use LKA to compensate for road conditions/handling. Kind of a separate thing.
All I was suggesting is that the "Active Pull Compensation Learned Limits" is pre-biasing steering using the same hardware as the LKA function.

Are you suggesting that there is a separate hardware system (from the one that does LKA) that can pre-bias the drive-by-wire steering?
 

·
Registered
Joined
·
549 Posts
I read about Bosch Active Pull Compensation and it said that it is supposed to watch the amount of torque being applied by the driver and compensate. When driving straight, if you have to apply constant torque to the steering wheel in one direction, it is supposed to compensate for that. So... if that's what it is supposed to do, it obviously doesn't work. :)

Mike
 

·
Registered
Joined
·
2,611 Posts
I read about Bosch Active Pull Compensation and it said that it is supposed to watch the amount of torque being applied by the driver and compensate. When driving straight, if you have to apply constant torque to the steering wheel in one direction, it is supposed to compensate for that. So... if that's what it is supposed to do, it obviously doesn't work. :)

Mike
Interesting.

Hypothetical: I commute to work every day for a year or two on a highway with a significant central crown. I unconsciously and constantly provide a bit of steering input to the left to track straight. The Active Pull Compensation (APC) detects the slight constant left steering input over a long period of time, and compensates by essentially applying a bit of left steering "trim" to unburden the driver.

Fast-forward, and I've moved to a different area where the highways don't have nearly the same amount of central crown. Now my vehicle wants to track left because of the APC.

I guess one can simply wait for the APC to adjust itself over time to the newly detected constant driver input to the right, or...get the APC data cleared by a service visit to eliminate the left pre-bias.
 

·
Registered
Joined
·
4,551 Posts
I read about Bosch Active Pull Compensation and it said that it is supposed to watch the amount of torque being applied by the driver and compensate.
The Bolt uses electric power steering, so anything off in the electronic system which applies force to the steering wheel would be suspect, I'd imagine. I think GregBrew is right, there's probably one steering wheel actuator which takes input from multiple sources.
 
61 - 75 of 75 Posts
Top