So - lately this has been happening every time I drive, it used to just be on occasion.

(93 LT1) I'll be driving along and the Low Trac light will come on - I'll step on the brakes and it will feel like there's something stopping the brake pedal from moving, but I'll push harder and it will eventually brake. Also - I'll notice some sort of rubbing noise from the drivers side of the engine bay. Shortly after, the light will turn off and the braking will go back to normal and the noise will go away.

What is this??

 

does the abs inop come on after it happens 3 times? something similar happened to me (the hardness of the pedal when stopping and then it braking normally) and it turned out i needed new pads/rotors.

 

sounds like a brake / abs problem to me..in-pending crash if not fixed..

 

The ABS light has been on/flashing since i bought the car two years ago.

I don't see it possible being the pads/rotors. Idk, I guess I could take the wheel off and have a look?

Edit: also, my brake booster went out about a year ago. Never replaced it.

 

i know they say brakes just slow you down but not replacing the brake booster..come on man..and yes pull the wheel and at least look..

 

well after i bought my car in 04 i found it had an intermittant low trac/abs inop problem like you described (although there was no weird noise) and then i had a blowout on the front right tire and the ABS problem went away for a month or so. I took the car in for a tuneup and had them check the brakes and they said the front rotors were a bit warped and the pads were down to 20-30% life. i changed all 4 rotors and pads and haven't had that problem since. The rotors had all been turned before so they had to be replaced.

My car would throw the low trac light during stopping in the last 5mph or so and the pedal would get really hard and then it would jump pretty far down and then come back up and after doing this 3 times the ABS INOP light would come on. it was kind of scary actually because you'd have to assume it was going to happen and brake early cause it usually took a few extra feet to stop.

 

Check your hubs in the front as I had a similar issue and it turned out to be a bad wheel speed sensor on the hub. If the ABS system senses one hub is turning faster then the other or it has a problem it will throw the low trac light and turn on the ABS.

 

where are the sensors? can they be cleaned or do they need replacement?

cant find anything on SHbox

 

The sensors are part of the hubs, here look at my pictures of one I took apart:





All it's made of is a basic magnetic pickup and unfortunately there is no way to tell if it's bad. On mine, I found after I removed it that the outer shell was slightly pop'd out from the hub (kinda like a lid not all the way on) and this was causing issues with the pickup being too far from the gear and therefore confusing the ABS into thinking the wheel was going a different speed. If you want to go this route pick up a hub (they are universal from side to side) and put it on one of the wheels and drive it to see if it make a difference. If not reverse the install and put it on the other wheel to see if the problem is there. You can always take it back to you local AP store and return it if you cannot solve your issue and you can get these off pretty fast (takes me 10 mins). Let me know if you need any help.

 

awesome post man, thanks for the pictures/advice! i will take a look this weekend.

 

Make sure to check all the connectors first to make sure one is not loose or freyed/shorted somewhere. Also, don't forget the single sensor mounted ontop of the rear diff and make sure it's plugged in as well and the connector is in good shape (3 sensors total - 2 front and 1 rear).