ABS Help please

[Sal Lubrano]

My 99 RX300 is having problems with the ABS. When I go to stop the car The brake pedal pulses. For some strange reason the abs is kicking on. It will do it on the highway, streets, light stop or hard stop. It does not do it all the time but does it very often. The ABS light is off on the dash so there is no code stored. I know the bulb is good because it lights up when I start the car. I am guessing a fault wheel sensor but how can I troubleshoot this better. How do I troubleshhot a problem like this if there is no light on saying there is a code?? I want to but this only if it is going to help? Actron®
Thank You for the help.
Sal

 

[DailyDrifter]

Wheel speed sensors could have debris on them, or possibly your ABS ring might be cracked(doesnt happen to often). Does it do it when you dont touch the brake at all? You could hook up a Graphing meter and see if there are any cracks in the ring, also see if the patterns are the same for each wheel speed sensor. OR take it to a toyota dealer and have them put a Factory scan tool on it to troubleshoot.

 

[Sal Lubrano]

No it does not do unless I press the brake. One more thing is it happenes for a brief period it does not continue through out the complete stop. No matter how light it is pressed it will do it. I am trying to not take it to toyota. Thier rates are really high. I would rather spend the money on my personal scanner than pay thier rates.

 

[TR Custom Parts]

Watch out on that brake scanner. Be absolutely sure that your car is on the list of vehicles it will work on. Bought one for a 98 Grand Prix after quickly reading that it works on 96 and up all makes and models but guess what, not on Grand Prix's.

 

[DailyDrifter]

I can see why you dont want to take it there. I'm not sure about the lexuses but some toyota's have to have the wheel in the right position because of yaw rate sensors and whatnot. Did you do any work to it recently, run something over.

 

[Sal Lubrano]

No the car did not hit anything. I was thinking. If there was a problem with the computer or pump or wheel sensor I would have an abs light on. I am thinking there is either metal filings on the sensor or the reluctor ring has a broken tooth. I am going to have to pull all the tires off on by one and pull the drive shafts in this dam weather. Or mabay I will cheat and pull the wheel sensors and rotate the tires and look down the hole.(Very cold here) The things we will do to save a buck.

 

[DailyDrifter]

The things we will do to save a buck.

Aint that the truth . Your on the right path, do you know anyone with a lift, or a heated garage .

 

[steve hughes]

On late model Chevy trucks rust builds up under the abs sensors pulling them away from the tone ring. Creates enough air gap the sensor thinks a wheel is trying to lockup on brakeing. I had the exact same problem you are going thru. Pull all the sensors and clean the crud off the hub where they mount.

 

[gunslinger]

Check the rear rings first. You can kinda see them from underneath. I've seen a few now with cracked rings causing low speed ABS stops.
Now the bad news. I haven't been able to find an aftermarket source for the rear axles of rings....Lexus price...$800 and last time I called, the LR was on national backorder.

Sorry

 

[Sal Lubrano]

Gunslinger. You must work with these cars often. I checked rock auto and for under $80 I can get either front cv shafts full rebuilt but to my surprise they don't even have the rear. LOL. When i get under this car I will let you know but with my luck I know it is broken. Probally just going to disable the ABS so the car is safe to drive and then go on hunt for parts. At least the car will have standard brakes compared to the - oh pedal stop vibrating I am going to soil my pants if this thing does not stop. Will let you everyone know if the ring has a problem soon.

 

[machinegun]

Metal shavings might cause this but a broken tooth would more than likly set off the ABS light as the sensor would read incorrectly. At least mine did even when the ring around the half shaft just cracked it ent the ABS into a tizzy.

Sounds like you have a speed sensor that is reading a littl foo kilter but not enough to set off the ABS warning.