ASR question

[AggieVette]

I frequently get a buzzing sound when backing up in my 93 coupe. Is this the ASR activating? I also get the ASR light when I accelerate from a stop. I'm a conservative driver, so it seems rather sensitive. I've started turning it off when I get into the car. Is this what everyone does?

 

[Tuna]

By frequently, do you mean right after start-up?

There is a buzz in the ABS system as it does a 'selftest' after each and every start-up. This occurs at 4MPH whether you're backing or going forward. Is this what you are hearing?

As for getting the ASR light while accelerating: The early systems are way to sensitive and activate the ASR more quickly than the newer systems. 92 was the first year for ASR - it gets in the way pretty often. Is you car an automatic?

I would not turn off the ASR everytime. If it is working properly, it will save you butt in low traction situations. It will definitely make the rear tires last longer also.

Please add more information about what you are experiencing.

 

[lew]

Tuna,

I agree with you, I never turn my ASR off unless I am very much in the clear of any solid objects. It is real easy to break the back end loose with the ASR off. I have also found it is possible to accidently swing out the back end with the ASR on, if you accelerate fairly hard from a stop while turning.

Lew

 

[AggieVette]

I think you are right about the buzzing. It only occurs after I start and proceed to back out.

I do have an automatic. The ASR flashes when I accelerate hard from a stop and make a turn. I feel a resistance from the accelerator. It doesn't happen all the time. I just wanted to find out if this sounded normal.

Thanks for the warnings about turning it off. I will be selective when I do it.

 

[Tuna]

I think you are right about the buzzing. It only occurs after I start and proceed to back out.

I do have an automatic. The ASR flashes when I accelerate hard from a stop and make a turn. I feel a resistance from the accelerator. It doesn't happen all the time. I just wanted to find out if this sounded normal.

Thanks for the warnings about turning it off. I will be selective when I do it.

It sounds like your car is working normally.

The ABS control box is behind the drivers seat and the self-test buzzing is more noticable when backing after start - probably because you're going slower rather than accelerating directly to speed.

As I mentioned earlier, the early ASR systems are prone to jump in quickly to limit wheel spin. Your 93, like my 92, jumps in very early compared to my 03 which lets a lot more wheel spin happen before it checks it. (see some of the C5 threads here in the CAC about people discussings this - it's just the opposite of what you are experiencing).

You'll get used to the pedal pushing back at you and you'll learn when to expect it. After a while, you won't really notice it - except maybe when you think the road has more traction than it does.
12 years ago when I bought my 92, the first time the ASR activated and the pedal pushed back against my foot, it made me jump right up in the seat. I had never had a car do that before - I knew it would do it and I still jumped.

Have a great holiday season.

 

[c4cruiser]

When the ASR system was introduced on the 92's it was GM cutting edge stuff back then. Here's some summary information from my 92 GM Service Manual.

The ABS/ASR system does a self-test whenever the engine is started and the vehicle speed reaches 4MPH in either forward or reverse. That's the sound you hear and is normal. The ASR system will function up to maximum vehicle speeds.

The ASR system uses a number of things to help control the car when activated. Depending on input from the lateral accelerometer (located in the center of the dash) the system can briefly retard spark timing, close the throttle (the pushback on the gas pedal) or apply brake pressure to the rear brakes. The system can also apply all of these things at once depending on input from wheel speed sensors and the accelerometer.

I usually turn ASR off in normal street use as the systems will use rear braking more than throttle control in some situations. That results in more pad dust on the wheels. I leave it on in cold or rainy weather. It stays off during autocross or trackday events.

I guess I still want to be able to control my car with brakes and throttle in "spirited" driving. The ASR system is a good one for the time it was available and the later C4's did get improvements in the system.