Z06 Whisperer

SORRY FOR THE LONGWINDEDNESS HERE, but I’m just trying to give as much detail (relevent or not ;p) as possible

This happened when I was most of the way into a 30 minute session during the second day of a three day event at Road America. I was going up the hill on the front straight and noticed the “service traction control” light on the dash.

(I had gotten that message before at an event recently when sitting in grid—turned the car off and on—and the message cleared. It did not return and there were no codes stored when I checked manually later. If I remember right I had changed wheels prior?) I had also changed wheels at this event but had already run a session with no problems.

We did however have trouble removing a driver's side rear wheel the day before. When it finally come off, it took off the ring and that large wire clip for the parking brake (which I do not use). We could not get the clip to go back in and after seeking advice, found poeple do run without it in.

Back to the story:
Then I got the message “service abs’ going up the front straight and it would alternate back and forth between that and the service traction message. I had never seen the abs one before, so I went into turn one a bit more conservatively. I didn’t notice a difference in braking so then went into T3 harder and still did not feel a problem. The messages remained.

So being stubborn (stupid:p) like I am I go flying all hell’s bells into 5. It’s a downhill sharp left after a long straight. I head in at 145mph+ and go to brake late as usual.

Well all of the sudden I’m braking and sliding forward like a nut!!!!! Fortunately I keep the car straight and where it's supposed to be on the track LOL. The car slows, but there’s this huge cloud of bluish smoke coming out the rear. I immediately put my arm out to signal I’m leaving the track and exit at five (makes me really appreciate the time I did autocrossing— it really helped me get around those four tire wall barriers at the exit real tight and quick LOL.

The poor husband was right behind me and I saw him exit right after me. He was really upset—thought I had blown the engine. We had just gotten it fixed from the last event –it was pretty stressful making seeing if it would be done, prepping a back-up car, etc. ( a broken timing chain resulted in damaged valves on my crate LS6 engine-we put in an upgraded chain, dampener and LS2 heads—4K on the credit card).

I get up to my pit space and my car is still smoking out the front. I keep reassuring the poor hubby that no it’s not the engine, it’s the brakes. People coming rushing up and tell me to keep driving it since it is smoking, which I do.

I get back and see the right front tire is A BIT corded.LOL I don’t have a photo hosting site or I would post a pic of it. We all figure it’s most likely the wiring for the ABS sensor on that wheel that is going or has gone bad? The wiring looked a bit suspect. We had no wiring replacement so the best we could do was pull the fuses (#52 ABS and #53 ABS Electircal) and borrow some used tires/wheels (thanks again Todd!!). This kept me out there the last two sessions, but because of the worn tires and testing to see what differences I could find with the fuses gone, I was really slow, maybe 8/10ths. The car seemed to handle okay at that speed however. I always drive the car with traction off—you know the one quick push of the button—not in competition mode, so I was already used to that part.

What the car’s display showed with the fuses pulled was “service engine soon” and the symbols for traciton off and abs off.

You would not believe the weekend we had been having prior to this either. The husband's Cobra threw a belt on Fri, so we had spent a bit of time going to different stores to find one, tons of calls, then he finds his second-time-replaced-under-warranty-(remanufactured)-alternator was bad too. After many more calls we found one. We had to pick up our son too that evening and we had one car left—he went down, got the parts, the kid and came back up—it’s 4 hours of driving.

We were up at the crack on Sat, got the alternator in and the Cobra was back in action! Then my car went down. I was going back to pick up the boy at the hotel in it at noon right after in his car and it started making a whistling sound upon acceleration— I came right back and the top had come off his catch can!

Hey I didn't forget the boy--I went right back for him after the problem was solved and even got take-out and a a back-up belt for the Cobra at NAPA.

So Sat night, I did the 4 hour drive in a borrowed Suburban (thanks again Mrs. H/Joel), Picked up my used replacement fronts, got Dan some tires and a few other bits and headed back. Now you all can not laugh at this ‘cuase I’m not at all a crier and if you call me a sissy I’ll kick your butts LOL, but when this one sad country soug came on on the radio I suddenly found myself shedding a few tears—OH shut up LOLOL).

Okay, fast forward to Sunday. My replacement wheels/tires are on and I start pushing to car. I used to not really get into the ABS that much, but I think more recently I had gotten lazy or more willing to use it when needed. It did remember in the past which turrns I would see it flash “abs active” and tried to be very vigilant when braking there.

It was really useful to go back to braking like I used to/should—almost just with my big toe. I exagerate, but not by much. I don't need to be stomping on it without feeling actually what was happening as I applied the brake pedal to varying degrees.

All was gong well until my subborn/thick headed streak showed itself again.

I was behind a car for almost two laps that had refused to give me a pass—the driver had been flagged by the corner workers muliple times and I had signaled the corner workers twice he was not giving me a pass. Found out the driver had given others a pass signal then would race them and not let them around. Same deal with me—the racing part.

I really didn’t want to get right on him because I wasn’t 100% experienced in how my brakes would repsond. I finally got a bit impatient though and got pretty close thinking he would finally let me 'round. Nope! He came in hot into the turn and I ended up having to brake hard. Let’s just say I can give you a real good description of his door handle. I did manage to stop and only have my left front tire ony a few inches off track—there is that wicked gravel trap right there.

But of course I managed to flat spot all four tires this time (and leave a real pretty set of skid marks on the track LOL). After immediately looking behind me at the corner worker to see the yellow waving flag, then seeing another car pass by and finally, clear track, I was out of there in a full hustle mode.

I ended up doing 3 or 4 mores laps but kept the speed down to about 120mph. And even though the vibration from the tires was not that bad, I figured I did have to be able to drive myself and the boy home. Hey, the husband did return the favor and let me drive his Cobra on track for the last session (I had let him use my Vette for the first time on track on Fri when his car was down) and the vibration from my tires was only bothersome at low speeds (and when you really have to go to the bathroom) on the trip home.


Follow-up (serious)LOL part of the post:

~Anyone sles experience ABS problems like this? Cause? Solution?
~We’re thinking of switching the wiring from the driver's side to the passenger's to see if the wiring is indeed the problem before replacing it—good idea?
~Anyone drive with the abs fuses pulled? What exactly is being disabled/changed in the car with those fuses gone?
~This is just my opinion, but for me I would have liked to done more practice doing “panic stops” with no ABS before I would have felt comfortable being aggressive in traffic.
~Does anyone have experiece with their cars showing warning lights that truly are false or can be ignored?

This is hindsight of course, but looking back, nearly all that warnings my car has given me have been accurate (for example, pre Katech belt tensioner, I had the car shred the serpetine belt and my car gave me brief heads up on that one too.)

THANKS SO MUCH FOR LISTENING AND FOR ANY ADVICE, ETC?

Anita

AU N EGL

Service ABS - When I get this I change all four bearings and wah la- No more problems.

The bearings are not made for this hard cornering that we do. Nor are the brakes and ABS modules made for excessive heat of hard braking.

Take a look at your ABS wiring going into the hub. Might be some of that wire insulation has been melted and the wires get crossed and short out, giving you that Message.

Having brake cooling ducts is a must. Use Castrol SRF brake fluid also helps prevent brake fade or failure. If you have boiled your brake fluid, NO the ABS will not work and you get "Service ABS soon" message as well.

Road America and Sebring are very very hard on brakes do to the high speeds.

95jersey

I just wrote about the exact same situation in the Pocono post...

I was having my ABS. traction control, and active handling lights come on 20 minutes into my first session. The whole car was behaving strange and turns that normally don't phase the car were freaking it out. The brakes were also LOCKING up completely under just medium threshold braking. I mean locking up for like 20 feet!

I throttle back big time to keep and eye on the situation and surely enought I was trail braking into a turn I normally take a 95mph at say around 80 and the rear lock up and threw the car sideways for at least 40-60+ feet. It was pretty scary, but I stayed on the track the whole time. I wound up flat spotting ALL 4 tires that only had 3-4 sessions on them...down the drain, gone waste of money.

In the end I was going pretty fast sidways and was a total passenger, so it could have been worst, but because I choose to ignore the dummy lights, it cost me $1400 + the day's expenses.

In my situation, there was a short in the wiring to the rear ABS unit. The dealer told me that if the system loses communication with a single sensor responsible for ABS, it shuts down all the systems that are related and use ABS (such as traction control and active handling). I couldn't beleive how my brakes were locking up under such medium level braking. I think we have all gotten so use to ABS, and the systems have gotten SO good, we can't even tell when they are on. I think the days when you actually felt the pulse of the ABS are LONG gone and they have become almost undetectable!

Anyway, no matter how early in the day and how far the track, if you see the ABS light come one and stay on when you turn the car on and off...GO HOME! I am lucky I did not crash my car or worse, get hurt, but it was a $2000 loss with gas, the event costs, tires.

FasterIsBetter

I had a problem last April with the parking brake spring letting loose when I was changing the brake rotors on the rears. It is a bugger to get back in, but with some persistence and a little luck, I got it to pop back in and seat properly. Without going through the job of removing the parking brake drum (a major PITA project), you have to be very patient, use a couple of needle nose pliers, and examine the situation very, very carefully, and you can get it back in without taking the drum off.

That said, I read over and over that you can run without the spring in place. I can't believe that the missing spring was the cause of your probably. More than likely, a mere coincidence. Hopefully, you have taken the car in and had the ABS system checked out. Pad, rotors, brake lines, bleeding are all DIY jobs. IMHO, servicing the ABS should only be done by a GM certified tech. There is just too much at stake with the brakes to worry about whether the job was done right and whether they diagnosed it properly.

Now, to change the subject, the original post is a good example of the difference between men and women. If her husband had posted this story, it would have read something like this:

"I was on the track behind my wife this past weekend and damned if it didn't look like she blew her engine. She's a great driver and manuvered the car off the track safely (Whew! Saved me a bunch of dough on body work.) Turns out her brakes locked up on her. I think it might be the ABS circuit that went bad. Has anyone else had this problem and how should be deal with it?"

Statistics:
Men speak 7000 words a day.
Women speak 35,000 words a day.

Mars vs. Venus, I guess.

Cobra4B

A few weeks back at VIR I had the "SERVICE ACTIVE HANDLING, SERVICE TRACTION CONTROL, SERVICE VEHICLE SOON" message come up in my 2nd session on sunday. I reset and and cleared the PCM as I shot down the back straight.

I had just come through oak tree and power slid off hte turn for fun... that's when the car flashed the message. I used to get that once in awhile 3 years go when I had standard Goodrige SS lines, there were problems w/ the lines not grounding out and causing a buildup of static charge that fooled a wheel speed sensor. I swapped to Goodrige lines w/ AN fittings and hadn't had hte message ever again.

I suspect it was because I'm running 315/17s on 17x11 GS wheels all the way around... they're the same size and the PCM likes the fronts a tad smaller.

It never came back... and I run w/ everything off anyway.

Z06 Whisperer

Hmm I do notice that your number of posts per day is larger then mine however!

Seriously maybe you should be my editor

Z06 Whisperer

I very much appreciate everyone's input here. I hate to see other's had problems like this, especially your most recent occurance 95jersey (I read your Pocono related posts). I'm going to reread every post thoroughly and not tell you all any more long stories LOLOLOLOL

<---------Oh I'll try to change my avitar to pic of the corded front tire.

Timz06

You know, it is possible to drive without ABS, just don't mash the pedal to the floor at 145

Z06 Whisperer

Hey, I wan't doing too bad until the end!

95jersey

I went back to the dealer and told them they owe me a set of Hoosier tires and they looked at me and said..."no problem, you owe me for 3 rears, 1 tranny, 3 wheel bearings", I'll subtract the tires from the total. I laughed and said, ok you got me there and proceeded to hug the man!

Sometimes you win and sometimes you lose, but the goal is to win more often than lose.

Webz

FWIW

I've had the service traction control light come on ('00 coupe) at different times caused by two different reasons.

1) Stainless steel brake lines were causing static faults (codes showed wheel speed sensor issue which it was not). Replaced the brake lines and all was good.
2) This one may be hard to believe but I replaced the IAT sensor, fault went away and never returned. I searched for a solution for a while and found an obscure post referencing this. It was a $25 DIY job and it worked.

varkwso

I flatspotted one fairly new tire at Road Atlanta last month - it hurts.

I flatspotted only the left rear - had no indications of lockup or smoke that I saw. I did do a "please god stop" at T7 due to the silliness on track so I guess that is when I did it. The same car flatspotted two fronts at CMP in Feb - but I did get failure lights and felt the lockup that time.

I have 40K of gentle show car driving on the 02 ZO6 so I am pretty sure that cannot be the problem . But my bearings and wiring are still in great shape...

John Shiels

I would find by the time was into ABS even with my stiff suspension it is not worth upsetting the balance of the car that much. I have seen 3 sets of tailghts the last 3 years so I am no just cruising. Stay just above ABS and I think you will be faster.

99BlackZ51

Anita,

Sorry to hear about your continuing problems. Here are some things I learned over the years.

ABS issues are fairly common on the C5, as Tom stated above it is usually caused by the sensors in the hubs getting fried from brake heat and at tracks like Blackhawk and RA you get a lot of brake heat. Cooling ducts do help but the only real cure seems to be a BBK.

Do not assume that the problem is in the corner of the car where the lockup occured, if there is a problem anywhere in the system in will shut the whole thing down. A scanner that reads ABS codes will tell you what part of the system is in failure. With all else being equal the rears will lockup first w/o ABS, that is why you cannot stop as fast w/o ABS on a C5 unless you readjust the front/rear bias.

Another helpful tip that I learned on this forum is that if you have a code come up while on track you can turn the key to the start position to reboot the system and clear the code.

IMHO, if your ABS is out that should not keep you off the track, it is a great way to learn threshold braking! Slow your brake application a little and you will feel when you are starting to lockup then back off pressure just a touch. T5 at RA will cause the wheels to lock earlier than normal since the track is "dropping out from under the tires" with the down hill run as LG put it. You do also have to be more careful when trailbraking but it is a great skill to learn.

I hope this helps
Scott

johninar

Could be the EBCM. Mine went out last month.

Olitho

I have had a number of occassions where my ABS has shut down on the track. Most recently it was just this past weekend at a SCCA Double Regional. Yes, the brakes to work, but not nearly as well as when ABS is functional.

On my car, without ABS working, the bias to the front is incredible. Even mild braking, by racing standards, into corners is enough to get the front wheels to lock. My braking distances are substantially longer and forget trail braking because the fronts will just lock the moment I begin to turn-in.

Yes, you can stop, but at substantially overall lower performance.

FasterIsBetter

LOL Just havin' some fun with ya!

Two years ago, I had a problem up at Watkins Glen with the ABS warm-up warning coming on, not being able to switch traction control off or turn competitive mode on. Bled the brakes at the track and it went away, but did come back a couple of more times. After I switched to the Wilwoods (calipers, rotors, braided brake lines, pads), no more brake warning problems.

If you and your hubby are serious track folks, as it seems you are, consider getting a set of the Wilwoods. Mine fit the stock sized rotors, so no need to get new front wheels. They make braking much more predictable, and no more eating up pads and rotors every track event.

Just a thought.

Z06 Whisperer

Tom,
How often are you finding yourself changing the bearings? I do have brake cooling ducts and bleed the brakes after every event. So I should probably regularly check the abs hub wiring too, right?

95jersey,
Thanks for the additional info about what actually happens in your car when you get that kind of failure. You all may already realize this but I have a C5 Z and the LG Wilwood brake kit up front. Going through the codes at home here (I had to put the 2 fuses back in before it let me :p) I got from the instrument panel cluster (60-IPC) U1040-"loss of communications with TCS" and from the traction control system (28-TCS) C1277-"requested torque signal CKT malfuntion". I assume both of those resulted from the fuses beng pulled. However the other TCS code C1233 RF "wheel speed circuit open or shorted" I'm hoping is pointing to the initial failure in the ABS system? And that by switching the wiring to the left side, the code with throw showing that side is bad.

Do you (or anyone else) know if you have to drive your car for a certain amount of time or speed for the system to pick up errors?

Anyway I'm pulling for you to stay on the winning side for at least the rest of this year!!

FasterIsBetter,
Thank you for providing more info about what I'd heard re:whether the parking brake clip is necessary or not. Now I just need to learn the replacement trick--hopefully it's not like one of those wire puzzles

And I may have the dealer give my car the once over before the next event too!!


Cobra4B:
Oh man I am so envious you can clear codes on the fly like that!! I once tried looked at my speedo in the carosel at RA because everyone's always talking about the speed they do going through there and were asking me mine. So of course I went on the inside grass a bit just taking a quick peek! I am curious about wheel size too because I do run different sizes/spacers or not depending on the best tyre prices/deals I can get! I know I really need to start bringing a notebook to the track and write things down like this!!


Webz,
Thanks for the additional paths to take if the original wire swapping idea fails. I do have stainless steel lines!?!?


varkwso,
Sorry to here someone else had some tires bite the dust!! I've never had wheels lock up before. The closest has been doing the fishtail/butt dance thing when you get on them hard. In my car I seem to notice that most when braking downhill.


John,
Yeah I know I need to get away from any ABS dependence, but it is nice in emergencies! Funny for years I drove (year round) my '88 5.0L Mustang (manual natch LOL) on all seasons (in the snow too) and that really helped me stay in practice for driving a pretty simply assisted car.


Scott,
I really appreciate getting advice from you because you not olny have driven the tracks I drive (a lot longer then I have), but because as a T1 driver it sounds that you are driving them actually with more restrictions on the use of "fancy gadgets" that many of the rest of us (DE'ers in particular) can add to our cars without any kind of rule/point assesment issues)--my upgraded front calipers as an example. Look forward to doing some more practice at F Body in Oct at RA!


johninar,
Again I'm glad to get any and all feedback and possible solutions, so thanks!


Olitho,
I'm very glad to learn of your experiences sans ABS. I had about 3.5 sessions to practice different braking times, distances, even different locations on the track (from side to side I mean). I could get the car to slide very slightly when stopping downhill, but not do the usual fishtail thing. I do feel better about my big skid into T12 now--like I'm not THAT bad of a driver. Yeah given the choice between abs or no abs, I'll take the abs--safer (and more control) for everyone around me and me!


FasterIsBetter,
Ahhh I can't even make a sassy comment back to you for your second post--I've got finger cramps after all this typing.

fatbillybob

I must admit my car is so flawless I have never had to do anything but gas oil brakes tires.

How do you do a pcm reset?

Thanks!!

Bill Dearborn

If you have a C5 race car you need to add a toggle switch in line with the power feed to the EBCM. If the system fails while on the track all you have to do is flip the switch to cut off the power and then turn it back on. The system will reboot and be operational again. Danny Kellermeyer has a switch on his cars.

Bill