Help! Autocross and ABS light
 

I went autocross today with alwan16.

On the last run by alex, the ABS light lit up. And of course the ABS shutdown, and the brake basically lock up easily, as he did plow some cones.
After that we let the car cool down. I shut off the car, turn the car back on, and the ABS light is not lit up anymore. Drove the car a bit, and the light is still off. I checked for leak, found none.
I think Alex can comment on what happened on the track.

Just a month ago, I replaced the following:
1. SS braided brake lines, you all know this story about the bad goodridge lines.
2. Install HP+
3. last week I put in new tires.

The brakes are good. Firm and not spongy at all.
We went autocross 2 weeks ago, and everything is good.

Now, I have some questions:

1. Would the ABS light lit up if you lock all 4 wheel at the same time?

2. Could there be air bubbles inside the lines, and work its way back to the ABS unit? The brake pedal is still firm, no spongy feel or dropping at all.

3. Would it be possible that it gets too hot? I don't believe this, because the day is pretty cool about 50+ degrees outside.

Thank you all for the help and thoughts...

Reza

The ABS went on during my last run. I don't think it was on when I started the course and everything was fine until about 40s into the course when I looked down and saw the 4 wheel ABS light on :(. As I came into the finish I slammed on the brakes and the front wheels just locked up and I went skidding for about 40 feet into the wall of cones ahead of me. Pulled into the grid area again and told Reza his ABS failed on me on the course. Good thing this wasn't on the street to avoid an accident. The light went off later when we turned off the car and started it again.

Anybody ever have intermittent ABS?

i have man. sounds like the same thing that happened to me at autoXes and even the street. its scary expecially when you get used to using hte ABS. i almost rear ended a viper but luckily it was one of the times that the ABS did work. i have a feeling it might do with the HP+ pads. they have a vast amount or IRON filings(carbon ferrous pads) and i think the iron shavings might magnetically stick to the ABS sensors on the wheels as they are also magnets.. can this be so???
kris

Alex,

I thought I saw the whole four wheel lock. because if only the front lock, the rear would swing out.

kris, what did you do to fix it?

Reza

to be honest i am not 100% sure. i dont even know if it was fixed. i took off the speed sensors and sprayed them with brake cleaner to get the metal off. it went away for a few to come back. after the car sat for a month with an oil leak then fixed it, i have yet to see it come back on. its good, but i want to know what the hell caused it
kris

The same thing happened to me on the street. There is an expressway entrance made up of a series of short straights mixed in with a bunch of hard corners near my house. I got the right front wheel to lock a couple times around it and then the ABS light came on and stayed on until I shut the car off. I'm pretty sure the right front locked BEFORE the light came on, but could be wrong. Regardless I wasn't pushing it too hard before that. I have EBC green pads (they don't dust).

As I have mentioned on several occasions the 16bit abs was replaced by a 32bit system on the 99 and newer cars. I think that would be a worthy upgrade if the cost isn't too high.

ABS should not let the wheels to lock. the only way it locked is when the ABS system shutdown, as we experienced last week.

Any comment from maxcooper/sleepr1 ?

Reza

i asked max awhile ago and he didnt have any clue. if anyone would know though, it would be max. also called rick's rotary and asked if he knew what it would be. he suggested that i tugged on my speed sensors when i changed my hoses and brakes. im usually very careful about this so i dont think its the case. Rick said that it would be a constant problem too, mine is intermintent. what pads are we(ones with ABS probelms) running?
kris

I just switched over to HP+
I am going to try clean the sensors off dust, and see if the problem come back.

Reza

im running the HP+ right now also. i cant see how it would come and go. i have a feeling that its the iron that is collecting on the magnetic portion of the ABS sensor. if only we knew for sure.
kris

i am gonna clean it before this weekend.
I will be running the car pretty hard in LA, so we can see if the iron dust will wreak havoc on the ABS. Hopefully not when I need it.

Reza

I have run the HP+ for a while and noticed the filings on the abs sensors as well. I have never had any brake or abs troubles but I do clean the sensors periodically anyway by just wiping them with a rag. I have never had any sort of brake malfunction on course.

I have doubts that dust is the cause for the reasons outlined above and the fact that my EBC pads produce VERY LITTLE dust. This is from the EBC website.

"EBC V4 Greenstuff

Triple Max Power Award winning Greenstuff are the ultimate performance/fast street brake pads you can get for your hot hatch or sport compact. These pads have a high friction coefficient, great initial bite from cold, right up to a blistering 650 degrees centigrade. . . Another major benefit of the Greenstuff compound is its award winning feature of being LOW DUST. Being awarded the UK magazines Autotrade Innovation Award for its low dust features, Greenstuff pads cut down between 60-90% of the dust common with most competitive types of semi-metallic pad on your alloys keeping wheels cleaner and delivering performance at the same time. "

maybe the iron came from the disc/rotor.
The rotor got eaten by the pads, the pads goes to dust and the rotors probably goes to bits, and some got stuck to ABS?

I am going to clean my sensors today. I ran the car, and test ABS by braking really hard until the wheels start grabbing and releasing, but so far no ABS light yet.

Strange huh...

reza

it is strange. you are experiencing the same thing i was. as for the iron coming from the rotors, not going to happen. iron is extremely heavy. to make a rotor out of iron would be, well, idiotic. hp+ reads on the side of the box, "CARBON FERROUS". ferrous would be a common way of saying iron. ferrous comes from Fe on the periodic table which i believe would be Fe(small 2). i suck at science to whomever corrects me thanks
kris

worse on me about science.
i always thought anything meta is iron.
because the country that I came from call metal "besi", while the translation for "besi" is iron
hahaahah

what is the rotor made of?

Reza

well from what i heard the kragen and autozone rotors are made of basically PLASTIC:) kidding... rotors seem to made of a steel. dont quote me on this though.
kris

Well, that's what brake rotors are made of. Hence the name, iron rotors :p:

I had EBC greenstuff on my 90 T2 once. They were sweet on-road and for autox, and they held up pretty well at VIR the first time I took the car there. The second time I was there, I got much harder on the brakes (and those pads grip like the hand of god when they're hot!) However, I overheated them and blew up a set, which had unhealthy consequences for my front rotors when the backing plate got on them...

Oh also to stay more on topic... the ABS in the Turbo 2s is junk. Learn to drive a little more conservatively and take that garbage out before it starts spraying brake fluid all over the inside of your engine bay.