Active handling problem
Thread Starter
Advanced
Joined: Nov 2003
Posts: 72
Likes: 0
From: oklahoma city ok
Active handling problem
I have a 99 FRC and I notice that the active handling is acting up at high speeds. During normal driving, everything seems fine. But, under hard acceleration at high speeds, it tries to correct the car when not needed. The first time, I had just reached about 165 in 5th gear on a really smooth straight road. Was not steering, braking, or anything except staying in the gas and going straight. The car felt like someone hit the brakes and jerked the steering wheel to the right. This turned me about 45 degrees, then released and allowed me to straighten the car. The next time was at about 120 in 4th gear. This time it just felt like someone tugging the wheel to the right and releasing a couple times. I did not notice the braking this time. The car does not have any unexpected movements with the active handling turned off. I would rather fix the problem than to turn it off. Any help is appreciated.
Thread Starter
Advanced
Joined: Nov 2003
Posts: 72
Likes: 0
From: oklahoma city ok
Originally Posted by MY1STPEWTER
Sounds like you just need to turn it off when you plan on going those kind of speeds. Nothings going to save your arze going that fast except the good Lord.
The problem is that I may forget to turn it off. I never plan to speed, since that would be illegal. But, sometimes I end up going faster than expected.
Burning Brakes
Joined: Jul 2004
Posts: 865
Likes: 5
From: Jensen Beach FL
I have experienced the same exact issue in my 2000 coupe (at similar speeds). It is definitely not a good feeling! I have not been able to find any type of malfunction in the system. I believe that the system as it is designed does not function well in extreme driving situations. In my opinion the AH is worse than useless, it is dangerous! If you are a competent driver and have a good feel for your car the AH will do nothing but hinder you. Turning off the AH/TC has become a habit for me. It no longer is even a conscious decision. I instinctively turn it off every time I start the car.
Perhaps the later version works better
Perhaps the later version works better
Thread Starter
Advanced
Joined: Nov 2003
Posts: 72
Likes: 0
From: oklahoma city ok
The repair shop said it is a brake locking up, which could not be possible since it only happens with the ah on. Just hate to forget to turn it off one day. Maybe its just another corvette problem that doesnt really have a good excuse.
Burning Brakes
Joined: Jul 2004
Posts: 865
Likes: 5
From: Jensen Beach FL
Technically the repair shop is correct. The problem is caused by the AH erroneously applying one or more of the brakes.
I think you are correct. This does seem to be one of those Corvette problems that really doesn’t have a good excuse.
Just try to condition yourself to turn the AH off every time you start the car. Soon it will become second nature. You will become so accustomed to seeing the amber light on the instrument cluster indicating that the AH is disabled, that if for some reason the light is not illuminated, it will immediately grab your attention.
I think you are correct. This does seem to be one of those Corvette problems that really doesn’t have a good excuse.
Just try to condition yourself to turn the AH off every time you start the car. Soon it will become second nature. You will become so accustomed to seeing the amber light on the instrument cluster indicating that the AH is disabled, that if for some reason the light is not illuminated, it will immediately grab your attention.
Melting Slicks
Joined: Jul 2001
Posts: 2,371
Likes: 5
From: Alamo CA
Turning the system off is one person's opinion. The system was designed with some pretty good engineering talent from the sensors up to the interface to the brakes. If it's not working right turning it off may be one option but talking to a knowledgable tech about the differences from year to year, they have improved the amount of leeway the system allows over the years seems like a better idea to me. I've had the system save the car at 95+mph through turn 1 at Sears Point when I dropped about a 1/3 of the right rear off the end of the burm, astounding save. The system when working is amazing, get some technical input, FWIW.
Randy
BTW, I had a code several months back and the local C5 expert updated the programming in the system from a GM tech bulletin, that was on a 2002. That also involved replacing the steering sensor and they checked the wheel speed sensors which I understand do go out over time. Like I said, it's not something to ignore. IMO
Randy
BTW, I had a code several months back and the local C5 expert updated the programming in the system from a GM tech bulletin, that was on a 2002. That also involved replacing the steering sensor and they checked the wheel speed sensors which I understand do go out over time. Like I said, it's not something to ignore. IMO
Last edited by StArrow68; Mar 3, 2005 at 11:55 AM.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
2027 Corvette vs The World: Every Model vs Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski
2027 Corvette Buyer's Guide: Everything You Need to Know!
Joe Kucinski
10 Things C8 Corvette Owners Hate (But Won't Tell You)
Joe Kucinski
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!
Brett Foote
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)
Joe Kucinski
Grand Sport & Grand Sport X Launch Alongside All-New 535hp LS6 V8!
Michael S. Palmer
5 Reasons Bad Drivers Crash & 5 Ways to Avoid a Costly Mistake!
Joe Kucinski
Burning Brakes
Joined: Jul 2004
Posts: 865
Likes: 5
From: Jensen Beach FL
I agree, that's just my opinion,to each his own. I have heard that for 2001 and new that the AH is vastly improved. I have had my system analyzed and everything checked out fine. The early model system is just overly intrusive. It will not allow me to “drift” the car at all. The instant the car settles into a nice four wheel drift, the AH (comp. mode) will activate and send me heading straight for the inside wall, guardrail, curb, etc. Without the AH the car will drift around the same corner wonderfully with no drama.
I have not had the opportunity to experience the AH on a 2001 or newer Vette. The only thing the AH on my 2000 is useful for is inclement weather.
I have not had the opportunity to experience the AH on a 2001 or newer Vette. The only thing the AH on my 2000 is useful for is inclement weather.
Melting Slicks
Joined: Jul 2001
Posts: 2,371
Likes: 5
From: Alamo CA
Since mine is 2002 I can't speak to older versions, but I've amazed a few by being able to get a little slide around corners, IF I work up to it and don't just throw it into the corner. Have to be very subtle and it works around the system, it does work but not with much leeway. It's also slower, I'm sure, just safe. On an older car I would like to know that the output from the wheel speed sensors and steering sensor are good but I don't think they have easy ways to test those. I don't know.
Randy
Randy
Burning Brakes
Joined: Jul 2004
Posts: 865
Likes: 5
From: Jensen Beach FL
Hahaha perhaps that is my problem; I have been known not to be very subtle! 
I’m the guy at autocross who is not always the fastest, but is always the most entertaining to watch! I know smooth is faster, but it’s not always as much fun…..
I believe that the output from the various AH sensors can be analyzed with the TechII.
The bottom line for me is: the AH has gotten me into far more trouble than I have gotten myself into (without it).
As stated earlier I would be very interested in trying out the later version. I would be very hesitant to test it out to the max in someone else's car though.........
I’m the guy at autocross who is not always the fastest, but is always the most entertaining to watch! I know smooth is faster, but it’s not always as much fun…..I believe that the output from the various AH sensors can be analyzed with the TechII.
The bottom line for me is: the AH has gotten me into far more trouble than I have gotten myself into (without it).
As stated earlier I would be very interested in trying out the later version. I would be very hesitant to test it out to the max in someone else's car though.........
Thread Starter
Advanced
Joined: Nov 2003
Posts: 72
Likes: 0
From: oklahoma city ok
Originally Posted by MGorman
Technically the repair shop is correct. The problem is caused by the AH erroneously applying one or more of the brakes.
I think you are correct. This does seem to be one of those Corvette problems that really doesn’t have a good excuse.
Just try to condition yourself to turn the AH off every time you start the car. Soon it will become second nature. You will become so accustomed to seeing the amber light on the instrument cluster indicating that the AH is disabled, that if for some reason the light is not illuminated, it will immediately grab your attention.
I think you are correct. This does seem to be one of those Corvette problems that really doesn’t have a good excuse.
Just try to condition yourself to turn the AH off every time you start the car. Soon it will become second nature. You will become so accustomed to seeing the amber light on the instrument cluster indicating that the AH is disabled, that if for some reason the light is not illuminated, it will immediately grab your attention.
Melting Slicks
Joined: Feb 2001
Posts: 2,137
Likes: 1
From: Oklahoma City OK
Cruise-In III Veteran
Some thoughts..............
Do you have any aftermarket parts such as sparkplug wires or stainless steel brake lines that could be emitting random electrical signals? Have you checked the wheel bearings? Could any of the sensors be loose? Some cars start to "float" above 140-mph, could your car be doing that enough to cause a sensor to activate? What about high speed air causing a wire to ground out?
Do you have any aftermarket parts such as sparkplug wires or stainless steel brake lines that could be emitting random electrical signals? Have you checked the wheel bearings? Could any of the sensors be loose? Some cars start to "float" above 140-mph, could your car be doing that enough to cause a sensor to activate? What about high speed air causing a wire to ground out?
Melting Slicks
Joined: Feb 2001
Posts: 2,137
Likes: 1
From: Oklahoma City OK
Cruise-In III Veteran
Some thoughts..............
Do you have any aftermarket parts such as sparkplug wires or stainless steel brake lines that could be emitting random electrical signals? Have you checked the wheel bearings? Could any of the sensors be loose? Some cars start to "float" above 140-mph, could your car be doing that enough to cause a sensor to activate? What about high-speed air causing a wire to ground out?
Do you have any aftermarket parts such as sparkplug wires or stainless steel brake lines that could be emitting random electrical signals? Have you checked the wheel bearings? Could any of the sensors be loose? Some cars start to "float" above 140-mph, could your car be doing that enough to cause a sensor to activate? What about high-speed air causing a wire to ground out?
Burning Brakes
Joined: Jul 2004
Posts: 865
Likes: 5
From: Jensen Beach FL
Originally Posted by 91VetteOkc
It is obviously applying the right side brake or brakes, but the repair shop thinks it is heating and locking up. Though, when it does act up, it is only with the ah on. I am just not sure what is signaling the brake. There is no turning g force. Just hard acceleration in a straight line.
What's signaling the AH to brake? That's the $100,000 question. I have not been able to figure it out. All the sensors etc on my car check out fine. Mine will actually apply the rear brakes from side to side causing kind of a fishtailing motion. As with you, this happens at high speed/ acceleration while going straight. I've tried to figure out the cause with no success. To tell you the truth, the last time this problem happened I was wide open near the top of fifth gear. It scared me so badly that I will never again be comfortable driving with the AH engaged. Even if I somehow determined that there was a proble with the AH and repaired it, that doubt would always be in the back of my mind.
Thread Starter
Advanced
Joined: Nov 2003
Posts: 72
Likes: 0
From: oklahoma city ok
I have the car in the shop to have my new trans, clutch, and 4.10 rear installed. The differential mounting bolts to the frame were found to be loosening, which I was noticing the slack for about the last week. I am not sure if this could have caused a problem. It did not act up when cornering hard or accelerating hard at lower speeds. But, I will also have that doubt that it will work properly at high speeds. I would rather turn myself sideways at 100+ mph than it to happen unexpected. Have any of you who experienced the problem noticed any slack in the rear mounting?
