abs pump assy

[arnea]

I just replaced the ABS pump assy on my 1992 Buick Lesabre. I bled the master cylinder but still have an ABS light on. The shop manual doesn't talkabout priming the assy. Is there a procedure. Thanks Arne

PS> the Brake pedal goes all the way to the floor...

[C man]

You have to bleed the whole system of air since all of the lines were opened when u replaced the abs pump not just the master cylinder. I did an ABS pump replacement on my buick a couple of weeks ago. Bleed the whole system using one of those hand vaccum pumps to make it a one man job. Also did you test the ABS pump before you got it to make sure it was good? Because it could be bad itself and have a internal short.

[arnea]

OK. I'll bleed the rest of the lines. I did not test the unit. How do you test it??? arne

[Jrs3800]

Bleed the system at all of the lines on the ABS Pump.... Then go back and bleed the system at the master cylinder.... Once the brakes feel good you can then take the car for a spin... If the ABS light is on as soon as you start the car then you have an internal...

Almost forgot, what car and year was the ABS Pump from or was it a new/reman unit?

[arnea]

So don't bleed at the wheel but right at the 4 lines of the ABS unit.... The unit is off a low mileage buick lesabre. 1994. I have 1992 Buick lesabre. The unit was identical to the unit I took out. The original pump had bound up...

[Jrs3800]

Here is the deal.... 92-93 used one ABS Pump, 94-95 used another.. There is supposed to be a difference... I was able to use another 95 unit on my 95 Bonneville..

I believe that 91-93 is the same unit..

Generally its good to bleed at the wheels, when you replace the ABS pump on these its not required unless you had the fluid drain out of the lines..

If you want to bleed at the wheels I will tell you to go ahead and do so as you'll have fresh fluid in the system all the way out to the wheels..

But if the ABS Light is on as soon as you start the car and stays on... There there is still a problem and you will have no ABS..

Here is my old unit...lol

Generally what happens is one of the inlet or outlet pressure sensors fails causing the EBCM or EBTCM to default Off turning the ABS light on.. Driving here in FL ABS is pretty much a must..

[arnea]

The pump assy is definitely dry and needs to be bled. Would this be the cause of the anti lock light being on at this point???? or do I have another problem????

[Jrs3800]

Originally Posted by arnea

The pump assy is definitely dry and needs to be bled. Would this be the cause of the anti lock light being on at this point???? or do I have another problem????

Is the clear reservoir on the ABS pump filled with fluid? If it is an the light is still on you may have another problem..

[arnea]

I'll have to check.... If it isn't...How do you fill it????

[Jrs3800]

Originally Posted by arnea

I'll have to check.... If it isn't...How do you fill it????

You don't.... There is a Hose from the ABS pump to the Master Cylinder, when you fill the master cylinder the ABS pump should fill as well.. But I want you to make sure its filled with fluid as if the level sensor in the unit is not happy this will also trigger the ABS light

[arnea]

Got it... Let me get to work...Thanks arne

[C man]

From my understanding the 92-95 pump assemblies are the same. I went to partsamerica.com and the ABS pumps assemblies is listed as the same for many H body cars from these years when you go to the vehicle that the parts fit. Were i live people can't drive so ABS was a must do on my list because I have had a many close calls as my car liked to loose traction from the rear during hard braking wet or dry. Also there is a thread in the century forum on testing the ABS for internal shorts for this ABS system in case your problem doesn't get solved by bleeding the system.

[C man]

Here's the link to test the pump http://www.automotiveforums.com/vbul...d.php?t=919080

[arnea]

Well I bled 3 out 4 wheel cylinders until the LH front bleed screw snapped. Oh well.... I did notice on the first 3 I didn't sense any air in the line. I have an abs scan tool and picked up a ton of codes. like all the speed sensors so I cleared the codes and now I have no codes but the abs light is still on and the brake pedal is still soft to the floor. any idea why the light is still on with no codes??? Thanks Arne

[C man]

Obviously you still have air in the system and how did you bleed the system. Now on the other hand have you also done a rear brake job, becuase if the rear shoes aren't ajusted right it will cause a spongy brake pedel feel. Also if you can drive the car for a short trip as the unit test itself soon afer start up and see if any codes come up from there and back track from there. But really test and see if the unit itself and see if its bad it's pretty simple.