Allpar Forums banner

1 - 7 of 7 Posts

·
Registered
Joined
·
5 Posts
Discussion Starter #1
Warping rotors every 30,000 mi, no abs trouble light in the dash. I verified the abs dash light works. Rotors, brakes, calipers, master cylinder, and front brake hoses have been replaced.

The system has also been bleed. I think it's a teves mark 20 abs system.
R Rear disk
L Front disk
L Rear disk
R Front disk

I don't have a DRB scan tool to do the programmed abs bleed procedure.

All 4 wheel speed sensors measure a resistance of 1.7-1.72k.

Tried ceramic pads and drilled rotors, same issue. The brakes and abs system all function with no noticeable issues until it eventually warps the rotors. I don't loose any brake fluid in the system over time. The brake pedal activation stays firm not soft. I think that the brakes are staying on just enough to where I can't tell.

Could the system just need a bleed with a DRB scan tool?
Even with no trouble light on the dash, possible the abs ecu or hcu is causing this?

Thanks!
 

·
Registered
Joined
·
8,047 Posts
Probably a stupid question, but I'm going to ask it anyway. Any chance you're overtorquing your wheels and other brake components?
 

·
Super Moderator
Joined
·
21,370 Posts
ABS shouldn't cause rotors to warp. The ABS bleed feature on the scan tool is mainly for bleeding the HCU (hydraulic control unit) if it went dry or was replaced. Conventional bleeding should work otherwise. Was the system opened or hydraulic components replaced at all?
Are the rear disc calipers frozen or stiff? This would make the fronts do all or most of the work in stopping the car. If there is a hydraulic combination valve that meters fluid to the rear, it may be faulty? The heat from this work can warp rotors. Is the parking brake cables part of the rear caliper function?
Are the rotors pitting (usually on the inside surface)? Are the caliper sliders and pistons free to move? What kind of driving does the car see? Drilled rotors sound like overkill.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #4
Wheels were hand torqued with a torque wrench in star pattern to 95 ft/lb. Hand torqued all the caliper hardware to spec as well.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #5
Nothing has been opened on the hcu or proportioning valve; the system was opened for the caliper, front brake hose, and master cylinder replacement. It's usually the front rotors that warp first, if I let it go too long it'll just heat up and lock up the caliper. I've replaced the calipers a few times but when replaced do verify the cylinder is free to travel.

The rear calipers have never locked up but the rear rotors have warped. The drum parking brake in the rear disk rotors have plenty of padding left, no burnishing etc.

No pitting is occurring on the rotors.

I just replaced all the rotors and brakes, also one front caliper.

Whenever I do a replacement I verify the calipers actually move.

Pretty light duty driving, just short trips in town once a week or so.

Maybe the front rotors think the rears are engaged/braking? I believe the rears are supposed to come on first before the fronts will start braking.
 

·
Super Moderator
Joined
·
21,370 Posts
If the front is heating up and locking the caliper on, you have either a hydraulic or mechanical problem. One or both of the front brakes are dragging, maybe more so when warm. Hot brakes still should not drag.
Get the brakes hot and find out which side is bound up. Sometimes a simple feel of the left and right wheel will tell you if one is much warmer than the other. Open the bleeder screw to see if a spurt of fluid comes out and releases the dragging brake.
4 wheel discs should all 'grip' evenly and at the same time. Make sure that all 4 brakes work by trying to turn the wheel when off the ground with the pedal 'lightly' depressed.
If the m/cyl was for a disc/drum system and the brake circuit is diagonally split, the wrong m/cyl could cause one front to stay on. Drum w/cyls require a constant residual fluid pressure.
The hub that the rotor mounts on should be sanded clean for good heat transfer and a true surface to mount to. Same with the inside mating surface of the wheel to the rotor. You want a clean, corrosion-free surface to sit flat against the rotor surface for best heat transfer and no uneven 'pressure points' against the rotor that may create a run-out condition after awhile, even if the lug nuts are evenly torqued.
 

·
Registered
Joined
·
5 Posts
Discussion Starter #7
The car is now showing an abs trouble light (mil). I've got code 11 and 12, saying both front wheel sensors are bad. It seems unlikely they would both just fail at the same time. I am getting a resistance of 1.6K when I checked the front sensors today. When I spin the wheel the resistance does change. Traced the wires back to the ecu/hcu connector, no open connections, everything tested ok.

Bad ecu/hcu?

I will try to clear the codes tomorrow and see if they reappear.



Also for anyone trying to access the ABS codes on a 1999 Avenger or Sebring coupe, do the following:

1. Make sure the ignition is off.
2. Find the 16 pin obd-II connector near the console on the driver's side.
3. Jumper pin 1 on the 16 pin obd-II connector to ground, (NOT the 12 pin Mitsubishi connector).
4. Turn the ignition on, (DO NOT start the engine).
5. The abs light will now blink the type 11 trouble codes in the dash panel mil.
6. Long blinks will be values of 10, ie 10, 20, 30, 40, and etc.
7. Short blinks will be values of 1, ie 1, 2, 3, 4, and etc.
8. For example, one long blink + four short blinks would = 14.
 
1 - 7 of 7 Posts
Top