"Anti-Lock" Blinking?

[RedZMonte]

What does this indicate. I figure my ABS is not working but what are the potential causes. it did it the other day then went off. then again yesterday and after sitting for a couple of hours it went off agian.  would low fluid do that?

Shane

[R Dubya]

My 89 does it all the time.  I read in a thread the Jeff M. replied to, said it was the Accumulator.  A good way to check I suppose is to turn the ignition on with the car off.  Press the brake pedal, and if you hear the PMIII run, then the acc. is leaking.  It keeps the fluid at a certain psi and should keep the pump running from anywhere from 2- 5 presses of the pedal.  I hear the PMIII everytime I press the pedal, which I hope is just the accumulator.  Anyone have any other info?  

BTW- called Prior - price on a new accumulator is $99.95, as opposed to GM PartsDirect - $223 + shipping.  Not Delco, but hey, it's also not $300 shipped.

[LukeZ34]

Where's the accumulator at? My Anti lock light stays on almost all the time.. I'll have to try pressing the brake a few times with the car off to see if it reacts how you described it..

[R Dubya]

From what I understand ( by no means am I a pro) but when the light is blinking, its not a critical error and the system will still work.  If the anti-lock light and the red brake light come on often its a more serious problem, but from what I understand, you need a scantool to diagnose properly.

[dave90tgp]

if you look at the master cylinder, the accumulator is a black ball with yellow markings below and to the left .

[LukeZ34]

ohhh.. ok, I know where it's at now..
If it is defective.. how hard is it to replace?

[turby]

If it is defective.. how hard is it to replace?

Relieve the system of any pressure. Unbolt the heat shield to give you more room. Take a ratchet, ext. swivel and socket and unscrew the accumulator. Installation is the reverse.

EDIT:
Here is a good link to read. (Credit goes to Chris A.)

http://aldridgec.home.att.net/TGP/brakes/powermaster.htm

[LukeZ34]

that's not bad at all.. looks like the bleeding is the hardest part of the job..

[bmktrexpro]

Where did you find the acc. for $99. The old part # that I have says $89, but then it gives me another part # and the price is over $200.

[TGPilot]

Where's the accumulator at? My Anti lock light stays on almost all the time.. I'll have to try pressing the brake a few times with the car off to see if it reacts how you described it..

Luke...the accumulator is brand new on that car. Check the wheel sensors first. It sounds like it is much more constant then when I had the car. If the light came on I would wash the car and the light would go out. I think there is a faulty wheel sensor. Which one I couldn't say... 8)

[The Burning Rom]

Where did you find the acc. for $99. The old part # that I have says $89, but then it gives me another part # and the price is over $200.

Prior reman. sells the accumulator for $99.

[sleeperred90tgp]

Just to let you guy's know there is another common problem with the pmlll
The rear pump housing leaks, closest part of the pump to the firewall, its an alum square about 2 1/2 sq. Mine leaked for yeas and then the dam broke. With that condidion you loose fluid but very slowly depending on the leak. Until the end I never had fluid on the floor and could go 6 mo to a year without refilling. The leak does the same thing as a bad accumlator, reduces pressure and trips the blinking light. Prior also sells the housing(machined from an alum tee)for about $260.00 or the whole unit less relay for about $700.00 now. Used to be $450.00.

ChrisA I think has a picture of this tee on his web site along with a bunch of other good info.

A point to mention is that the prior accumulator has the nut on the back near firewall not in the front. Never changed a Prior but it has to be a bitch. Might be eaiser to pull the pm. You might get it by slaving the motor and using a strap wrench. Anybody replaced one?

Bleeding tip if you are replacing your whole unit. These units are tested at prior and have fluid through out. Leave the brake lines off. Fill with fluid. Open the pm bleeding ports and get them to run clear fluid by the normal bleeding method(down, close, up) You will have fluid runing out of the brake line hole also. Push pedal down part way to insure fluid is comming out of the brake line ports and hold the pedal. A 2x4 works well using the power seat. Put lines on tight. Release brake. Loosen lines 3 to 4 turns, down and hold with the pedel observing the fluid for air. You might get a couple of bubbles. Tighten lines and repeat, You should now have clear fluid. Done correctly you won't have to bleed the lines. :lol:  :lol:

This has worked for me 3 times. Don't forget to keep the pm full.

Jud.

[Chris A]

Sounds like you guys have some good updated info on  Prior. I'll have to call them to get the most up to date pricing as it seems to have changed a lot.

They wouldn't sell parts before, but maybe with the difficulty in getting cores they found it better to sell the parts seperately.

Chris

[bmktrexpro]

Does anybody have a phone # or web address for Prior?

[Chris A]

Sure,

Priorreman.com