traction control goes on randomly at right turns

[tookien]

Saab 9-7x 4.2L 2007

Changed the rear axle bearings.
Changed rear LSD diff oil (but did not include the GM additive, only synthetic 75w-90).

Changed front right wheel hub assembly (with new ABS wheel sensor) as a previous aftermarket wheel hub was defective.
Changed all rotors and brakes.

Problem is stailtrack/traction control (and light) flicks on (sometimes) when making long right turns at higher speeds. ABS light does not come on.


I noticed after changing the rotors the brakes felt a little spongy. I had to compress the calipers. I also bleed all the air in system afterwards. After driving a couple of days feels like it's supposed to. I think some air had been trapped in the ABS module. No loss of fluid or anything.

No noises at wheel bearings. No play at wheels. Everything is firm.

Which could be causing the issue more likely:

- lack of rear LSD diff GM oil additive
- defective front ABS sensor
- some air left in ABS module

 

[andyd]

Fix the spongy pedal. Read the bottle of lube you used. If it says to use as a top off only for LSD, then you need the FM. I would tend to these before replacing parts.

 

[jhellwig]

The stabilitrac/ traction control system on gm vehicles is dependent on the abs sensors. If one is getting weak and not producing a strong enough signal when the others are the system thinks it needs to act on it. You can read the sensors with a voltage meter and check their resistance. There are set parameters the should fit that can be found in the service manual.


I had this issue on a Tahoe with awd. There was a specific intersection that everything would line up right on making it think it was slipping which cause the throttle to pull back and brakes to apply to counteract the supposed loss of traction right as the vehicle was crossing lanes of traffic. Found a bum sensor on an aftermarket hub that wasn't that old. It didn't produce a high enough voltage fast enough.

Another thing that may need to be done is reset the yaw sensor. I have no idea where that would be in a sabb.

 

[tookien]

Originally Posted by jhellwig
The stabilitrac/ traction control system on gm vehicles is dependent on the abs sensors. If one is getting weak and not producing a strong enough signal when the others are the system thinks it needs to act on it. You can read the sensors with a voltage meter and check their resistance. There are set parameters the should fit that can be found in the service manual.


I had this issue on a Tahoe with awd. There was a specific intersection that everything would line up right on making it think it was slipping which cause the throttle to pull back and brakes to apply to counteract the supposed loss of traction right as the vehicle was crossing lanes of traffic. Found a bum sensor on an aftermarket hub that wasn't that old. It didn't produce a high enough voltage fast enough.

Another thing that may need to be done is reset the yaw sensor. I have no idea where that would be in a sabb.




but doesn't traction control have to do with acceleration and ABS with braking?

assuming that the sensor was bad (low voltage), wouldn't that also affect the ABS when braking?

my problem is that traction control only comes on during acceleration, specifically when turning to the right.



I had problem with sensor before, and it triggered both traction control and ABS.

 

[40w8]

I have a 07 Mazda RX8 with only 36k miles. I mostly drove it 1k miles a few times a year to HPDE track.

It seemed to start chirping the left front when turning left.

Later I noticed a wheel weight might be missing.

After 6 years of old worn Hankook Ventus V12 tires, I put new Michelin PSS tires on, and not a peep from front left anymore.

More traction, balanced, but same alignment which wore old tires very even

 

[clinebarger]

The wheel speed sensors are a fundamental part of the traction control system, The lack of LSD additive in a Clutch Style Posi can cause issues with one rear wheel wanting to skid going around a corner in wet/slick conditions.

Gear oil with LSD additive never has enough additive in it based on my experience.

 

[DoubleWasp]

Possible steering angle sensor issue?

 

[OilUzer]

I'm not a mechanic but a few things I've heard or read about over the years that may help:


1- just curious and in general, why didn't you add the lsd additive? I've read that it can cause chatter!
2- you didn't change tires i assume.
3- other causes could be wheel bearing, tire size and/or pressure, alignment,
4- any sensors nearby tires, etc. that you may have damaged ? I've heard tire places damaging sensors during balance/rotation causing traction control issues.

If it was me, I would fix #1 regardless if you didn't follow the recommended fluid.
#3 (Wheel bearing) could be a possibility!

To start with i would do #1 and check #4
Then maybe look into #3 starting with wheel bearing.

In brake department, drive a little, stop (easy on the brakes) and feel the rotors. If they are sticking, you can feel the heat difference. Try again with harder brake and see if anything glowing or not

 

[Kamele0N]

#3....do all tires have the same pressure...?

 

[antonmnster]

#4 ... do the tires match?

 

[jhellwig]

Originally Posted by tookien
Originally Posted by jhellwig
The stabilitrac/ traction control system on gm vehicles is dependent on the abs sensors. If one is getting weak and not producing a strong enough signal when the others are the system thinks it needs to act on it. You can read the sensors with a voltage meter and check their resistance. There are set parameters the should fit that can be found in the service manual.


I had this issue on a Tahoe with awd. There was a specific intersection that everything would line up right on making it think it was slipping which cause the throttle to pull back and brakes to apply to counteract the supposed loss of traction right as the vehicle was crossing lanes of traffic. Found a bum sensor on an aftermarket hub that wasn't that old. It didn't produce a high enough voltage fast enough.

Another thing that may need to be done is reset the yaw sensor. I have no idea where that would be in a sabb.




but doesn't traction control have to do with acceleration and ABS with braking?

assuming that the sensor was bad (low voltage), wouldn't that also affect the ABS when braking?

my problem is that traction control only comes on during acceleration, specifically when turning to the right.



I had problem with sensor before, and it triggered both traction control and ABS.



It is all tied together in one big complicated system. The issue I had never cause a fault in the system on any trouble lights to come up. Since you said you changed the hub that would be the first place I would look. Could be a bum new sensor. The reluctor wheel it is aimed at might not be in the exact right place. Something may have been damaged on the connector when it was worked on.