Help with 1999 Grand Prix GTP

[nyaklin]

We just purchased a used 1999 Grand Prix GTP in January. Was bought with 165k miles on it.

Shortly after getting it, the ABS light and the TCS OFF light came on and won't go off. From reading around here, it looks like it's some kind of hub or something. (Forgive me, I know very little beyond checking fluids).

Recently, a whining noise began. I believe this is unrelated to the above issue. It's coming from the passenger side. My husband believes it is the serpentine belt.

And just today it began making this horrid roaring noise upon start up and again once idling. Accelerating or speeding up makes it go away.

Sometimes turning makes the previous two issues go away for a few seconds.

We're at a loss. Thanks for any help!

[BNaylor]

Welcome to AF.

The hub assembly has the wheel bearings and wheel speed sensor.

On the noise issue start by checking your power steering fluid level.

[UKtech]

Originally Posted by nyaklin

We just purchased a used 1999 Grand Prix GTP in January. Was bought with 165k miles on it.

Shortly after getting it, the ABS light and the TCS OFF light came on and won't go off. From reading around here, it looks like it's some kind of hub or something. (Forgive me, I know very little beyond checking fluids).

Sometimes turning makes the previous two issues go away for a few seconds.

We're at a loss. Thanks for any help!

Your description of the noise going away upon tuning sounds like a wheelbearing starting to fail,when cornering/turning your shifting the weight of the vehicle and loading/unloading the bearing,with the weight applied the bearing genrally becomes louder and when unloaded becomes less noticeable...... as Bob said the wheelbearings come as a complete hub assembly which incorporates the wheel speed sensor for the ABS/Traction control ..... when a wheel bearing is worn it will produce excessive virbration which will casue the sensor to read in an erratic manner and in some cases go open circuit and the computer will disable the system as a safety precaution , when the ABS/Traction lights are on the system is disabled.

Does the noise become louder the faster you go ?

Check the front and rear bearings for any kind of play to start.

Good luck

[richtazz]

If the roaring noise occurs while the car is not moving, it could be a disconnected vacuum hose if you were poking around under the hood trying to find the whining noise.

I agree with Bob and UKtech that the ABS and Trac-off lights are most likely a bad front hub bearing, and they will also roar as you speed up as they get worse. It will sound similar to the sound a propeller driven airplane makes. The power steering pimp is in a lovely place, low in the back near the firewall, so getting to it to check fluid level is really fun. The power steering pumps on these cars are a pretty common issue to whine, so check the fluid level for sure. If low, look for signs of fluid getting flung about by a leaky front seal (the belt will be oily, there may be a "stripe" of fluid on the firewall and underside of the hood, etc...).

[BNaylor]

Also, keep in mind since this is a GTP and has Magnasteer (variable effort ratio) steering that most if not all GTPs have therefore ABS and traction control issues regardless of a hub is at fault will cause the steering to stiffen up at low speeds so getting weird noises is not uncommon due to the increased effort to control steering.

Technically, ABS and traction control issues should be checked with a scan tool capable of retrieving ABS/chassis codes. The codes will point you in the right direction or confirm if a hub is bad without guessing.