Brake issue (abs??)
Thread Starter
Burning Brakes
Joined: Jan 2004
Posts: 791
Likes: 1
From: lincoln ri
Brake issue (abs??)
I'll make this as brief as I can. 88 base coupe, right front caliper, slow to release causing excessive heat. Replaced caliper and brake hose, bled, same problem. Flushed fluid since it was pretty dirty, bled, same issue. Replaced master, don't know why, bench bled, bled system, same problem. Checked the fsm, followed procedure for checking abs. Only weird thing, turn key to on, abs chatters (under storage bin) once, anti lock light flashes on, then stays off. According to fsm, light is supposed to stay on with key in this position. I'm thinking, maybe a bad solenoid relay on abs. Attempt to unplug according to fsm instructions, it starts hissing and starts to smoke slightly. Stopped right there. Started car, anti lock light now stays on, same brake issue. My question if you made it this far, what the hell was this smoke? It didn't have the electrical odor such as arcing. Is this relay sealed with gas? I know I'm screwed and have to do the walk of shame to the dealer.......
Thread Starter
Burning Brakes
Joined: Jan 2004
Posts: 791
Likes: 1
From: lincoln ri
I'll make this as brief as I can. 88 base coupe, right front caliper, slow to release causing excessive heat. Replaced caliper and brake hose, bled, same problem. Flushed fluid since it was pretty dirty, bled, same issue. Replaced master, don't know why, bench bled, bled system, same problem. Checked the fsm, followed procedure for checking abs. Only weird thing, turn key to on, abs chatters (under storage bin) once, anti lock light flashes on, then stays off. According to fsm, light is supposed to stay on with key in this position. I'm thinking, maybe a bad solenoid relay on abs. Attempt to unplug according to fsm instructions, it starts hissing and starts to smoke slightly. Stopped right there. Started car, anti lock light now stays on, same brake issue. My question if you made it this far, what the hell was this smoke? It didn't have the electrical odor such as arcing. Is this relay sealed with gas? I know I'm screwed and have to do the walk of shame to the dealer.......
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
It's sounds like you going to need a another ABS modulator valve unit. Normally if the valves in the block are out of place it will set codes. Hissing and smoking is escaping electrons. Since the light is on all the time what code is set. Because of the age of the car I would call ahead, some dealers won't work on cars over 20 years old.
there is a old tread from 2/12 involving another 88 with same symptoms. couldn't pull the link, so search it. Good Luck
there is a old tread from 2/12 involving another 88 with same symptoms. couldn't pull the link, so search it. Good Luck
Last edited by Kevova; Dec 2, 2015 at 05:07 PM.
Melting Slicks
Joined: Jan 2014
Posts: 2,192
Likes: 381
From: Lunenburg MA
I wouldn't even think of taking my 27 year old car to a dealer. Find a good local mechanic who is familiar with older cars. From the sounds of it, you already needed another abs pump anyway. The solenoids generally fail from too much moisture in the brake fluid.
Thread Starter
Burning Brakes
Joined: Jan 2004
Posts: 791
Likes: 1
From: lincoln ri
#4 is the one that started hissing/smoking when attempting to remove
actual abs pump in car; silver colored relay is the one I'm questioning
Melting Slicks
Joined: Jan 2014
Posts: 2,192
Likes: 381
From: Lunenburg MA
This all started with a caliper slow to release (right front). I'm resigned to replacing the modulator valve (pump) if I can find one, but was just curious when pulling the solenoid relay off the pump, why I got vapor and hissing. Weird (to me)....Are the relay's pressurized with a gas to protect them? I'm going to try to upload a couple of pictures; one from the actual unit, the other from the fsm.
#4 is the one that started hissing/smoking when attempting to remove
actual abs pump in car; silver colored relay is the one I'm questioning
Thread Starter
Burning Brakes
Joined: Jan 2004
Posts: 791
Likes: 1
From: lincoln ri
Actually, was just pulling on the relay again. Smoke appeared, discovered that main loom of wire that connects to the computer was frying !! Don't know if it was shorting out against the pump, but this is turning into project from hell!! Disconnected everything except brake lines to pump. The other news is the right front caliper is still releasing very slowly even wit the abs disconnected. Could it be possible one of the solenoid valves on the abs stuck in the (mostly) closed position?????
Thread Starter
Burning Brakes
Joined: Jan 2004
Posts: 791
Likes: 1
From: lincoln ri
Agree with that!! My fluid looked pretty nasty, through my own neglect, lesson learned, will be flushing periodically now!! Abs electrical harness has been removed, wondering if possible for solenoid for right front could be stuck closed.....
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Thread Starter
Burning Brakes
Joined: Jan 2004
Posts: 791
Likes: 1
From: lincoln ri
Well, problem solved....For now....Replaced modulator assembly, caliper releases as normal. Hooked up electrical, abs light stays on. Replaced relay (the one with the clip that sits next to the 'computer'), abs operates normally. If this happens again, I will be bypassing the abs completely.