Intermittant (very rarely) ABS light coming on with shake at 65 MPH

[dullard]

Any idea what might cause this? My fiancee's 2000 Taurus has started acting up. She describes it as a mild shake and the ABS light coming on. Both occur simultaneously and both last under a second. It randomly happens (but not very often) at about 65 MPH. A mechanic friend had no idea and couldn't replicate the problem. My fiancee is terrified to drive it at freeway speeds until we have something fixed.

The mechanic scanned all the computer codes. Only one problem showed up - the computer that controls the lights on the dash had a one time low voltage error. That error may or may not be connected to the issue.

Thanks.

 

[thescreensavers]

the ABS might be kicking in which might explain the shaking but idk.

 

[amdhunter]

loose caliper?

 

[CurseTheSky]

It's a completely different brand, car, etc., but my 2003 Malibu was having similar problems for a while, which eventually turned into a constant grinding at all speeds. It ended up being a wheel bearing (the connector for the ABS sensor was on the unit).

$120 later, no more grinding and no more ABS light. You might want to look into that, just in case.

 

[PottedMeat]

Check the wheel speed sensors - one on each wheel with a gear behind the knuckle? Maybe one isn't the right distance from the teeth or there's some dirt/grime on the teeth?

 

[dullard]

Thanks for the suggestions.

 

[vshah]

is this while she is braking? or just randomly while driving?

 

[dullard]

Originally posted by: vshah
is this while she is braking? or just randomly while driving?

I'll ask, but I think it happened both randomly while driving and once while slowing from 75 mph to 65 mph for a construction zone. But I don't know if she was breaking at the time or just coasting slower.

 

[Pegun]

If it happens when she brakes it could very well be that she is low on brake fluid. Make sure that doesn't get overly low or you'll have to bleed the brakes.

 

[thomsbrain]

Are all the tires the same size/pressure? Differences in circumference can screw with ABS and TCS/ESC systems.

 

[dullard]

No problems so far this week. It is just too intermittant.

Originally posted by: thomsbrain
Are all the tires the same size/pressure? Differences in circumference can screw with ABS and TCS/ESC systems.

The tires are different pressure but the same size. She likes higher pressure in front and lower pressure in back. I'll let her know and try it with the same pressure for a while.

 

[Squisher]

Diagnosing this is out of my pay grade, but if it's a wheel bearing it couldn't be easier to check. Get wheel off the ground, grab it at 12 o'clock and 6 o'clock and feel for some play in the bearing.