Urgent help needed with ABS

maxmk8

Registered
Of course as luck would have it, after replacing the cracked rotors. I developed an ABS problem on my 98 Mark VIII. I drove for about 30 miles with no issues with the rotors. After I parked my car for a couple of hours and then came back to drive it, it felt like my ABS was engaging when I was just gently on the brakes. I could hear the abs pump going haywire in the front left side of my car.

The cars stopping ability was seriously affected.

Since I was far away from my house all I could do is just look at all the ABS sensors and see if they were damaged during the rotor swap. They all seemed fine with no visual damages. So I am guessing that it was a random problem that just correlated with the recent rotor swap.

I had to remove the ABS fuse in order for me to drive my car back home. Has anyone had a similar problem and what did it turn out to be? I never got the ABS light so I am not sure where the issue lies. Is there a self test that could shed some light on this problem?
 
I would clean the ABS sensor gear teeth before doing anything else. All sorts of carbon and junk gets caught in there.

If one of your sensors was bad or intermittant, it would have thrown a code and turned on your CE light. I've had that issue before. I unknowingly had created a small intermittant open circuit on one of my front ABS sensors while working on the car. It would only show up when I turned the steering all the way to one side. That's how I figured out which side was bad.
 
Can I use Brake-cleaner to clean the sensor or will it damage the hub an bearing if I am spraying that stuff in there?!

Funny you mention the turned steering wheel. It was fine for a bit and the I turned all the way to the left and it started up again.
 
Can I use Brake-cleaner to clean the sensor or will it damage the hub an bearing if I am spraying that stuff in there?!

Funny you mention the turned steering wheel. It was fine for a bit and the I turned all the way to the left and it started up again.

The reason the turned steering wheel can cause that is because the sensor cable on one side is stretched, which can reveal an open circuit.

As for the brake cleaner, I'm not sure. I've used a toothbrush to clean it in the past - no liquids.
 
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Thats kinda what I was telling Max when he was on the road. The brake lines are run kinda close to the ABS harness, so I was thinking that when I removed the front calipers and let them "hang" down on the lower c. arm, I thought maybe it pulled on one of the sensor harnesses and caused it to tangle, or stretch and get caught up on a hanger for something else. That was my first guess, secondly, the gear would have to be extremely dirty to have some issues and I remember looking at the inside of the passenger side rotor when I pulled it off and there was an excess of metal particles floating around the inside of the rotor hub. Maybe the ABS gear is dirty, but I'd make sure one of the ABS harnesses aren't stretched or pinched.

When I did my brake swap, I had one of my brake lines pinch my d.side ABS sensor when I first drove it, but it threw a code so it was obvious which side failed.

Max's issue kinda stumped me so as an easy fix while he was on the road I told him to pull the ABS fuse so he could get home.

Max....if you turned to the left...I would check the drivers side sensor because the harness goes to the front of the spindle so if you turn left it will be pulling it tight(like a tiger, lol).
 
Well 2 more hours until I can tackle this. I really hope that I will be able to visually identify the problem, ie see the damage to the wire or see it pinched. I really don't want to take the car to the dealer and having them diagnose it.

I read all the directions on how to pull abs codes etc. I will have my hands full tonite. If I remember correctly the drivers side was the caliper that god dislodged and started dangling... So all signs point to drivers side. I will post an update later.
 
Well 2 more hours until I can tackle this. I really hope that I will be able to visually identify the problem, ie see the damage to the wire or see it pinched. I really don't want to take the car to the dealer and having them diagnose it.

I read all the directions on how to pull abs codes etc. I will have my hands full tonite. If I remember correctly the drivers side was the caliper that god dislodged and started dangling... So all signs point to drivers side. I will post an update later.

Worse comes to worse, you can purchase both sensors and replace them one at a time to figure out which one is bad. Then you can return the sensor you did not use for a refund.
 
I cleaned both sensors and they showed no visible damage. I no longer have the vibrating pedal. But now I get a check traction control display every time I go faster than 15mph. My 98 doesn't have an ABS test port. So I am at a loss for now.
 
I cleaned both sensors and they showed no visible damage. I no longer have the vibrating pedal. But now I get a check traction control display every time I go faster than 15mph. My 98 doesn't have an ABS test port. So I am at a loss for now.

ABS and traction control are married in that single sensor.
 
Yes, I am familiar with the electronic structure. I am at a loss as to what sensor to replace since there are several and I don't know which one is malfunctioning.
 
Front Left wheel sensor pulled up on the code reader at a shop. I will be replacing it soon. Anyone know where to get the best price on it?
 
Front Left wheel sensor pulled up on the code reader at a shop. I will be replacing it soon. Anyone know where to get the best price on it?

Couldn't find any at Autozone, Kragen, Napa, or Rockauto.

You may be stuck with the dealer. I don't recall the price.
 
Yep I checked all three as well. Dealer list looks like it is only $35 and $25 something with a discount... I hope that is an accurate price. On hold with dealer right now checking on price.
 
Oh my... they are a dicontinued part since 2005 dealer says "go aftermarket, sorry I can't help". This is troubling.
 
Used....lol....this is what M8's have come to. BTW, I'm charging you for the weight of the sensor while I race, lol! J/k
 
Jamie wants $100 or I should say peter. I hung up on him.... that is outrageous. They buy Mark VIIIs for $100.
 
I am not about to get price gouged pay 3x for a used sensor what is worth new. No way. I found local junk yards that sell it for 1/2 the cost. I figured I would give our own guys business first but not at those prices.

I also filed a claim with the NHTSA... nearly 18000 1998 gen II Mark VIII owners will be affected by this. It is a safety issue for sure. Sad part is they are NOT interchangeable amongst the years or any other cars... wow.

end Vent. And of course all this BS happened right when I bought my Corvette. How do cars notice these things ?!
 
Normal machine jealousy. Didn't you know that machinery are animate
objects? Have two vehicles? Buy a new part for one car and see how long before you gotta repair/replace a part on the other......jealousy, I tell ya...
 
Lol! Seriously, thats how it is! When I bought my Mark, the Stang just sat in the garage(ticket magnet), so on the days I wanted to take it for a spin, the battery was dead.
 
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