I have a new to me 1997 Volvo 855 NA auto. I just did new plugs, rotor, cap, air filter. And I have a one small problem still. If I drive the car like an old man then everything is fine, but if I accelerate hard then the ABS light will come on, after the car is shut off and then turned back on it wont come back on until another hard acceleration.

Any idea on anything that I should be looking at? or is there a code reader that will tell me the error code on what it is?

Thanks in advance.

It might be this...
Check the brake fluid level in the Master Cylinder. There is a level (float) in there and under hard acceleration, the fluid goes back and cause the float to drop sending a signal....

Or it could be this: http://home.earthlink.net/~vicrocha/

it could just be the connecting block, mine does something similar and I cured it by wedging a couple of pieces of cardboard between the connector and the body of the pump, its an easy thing to try, but what the permenant fix is I am not sure yet.
Grendel

That was a good thought, so I topped off the fluid but it didn't change anything, thanks for the suggestion though.




Where exactly did you wedge something? Can you possibly take a picture of what you mean?

yes have posted this one here in the past.
Grendel

I'm going to have to try that tomorrow and see what it does. I'll post back if it works or not.

Well I tried putting in a single piece of cardboard there but the light came on. I have now folded the cardboard in half and wedged it back in. We'll see what happens next.

Well the light stayed off till a block from home after accelerating from a stop, but it was off for a good 8 miles? And a few fast starts. So I wonder if the module thing has cracked connections like I've read about. I could easily take it out and look at that I guess, and I solder well so that wouldn't be a problem but I donno, I'll check what it does tomorrow and then go from there.

Well, I'm back to square one. The cardboard didn't do anything for me after all. Its still doing the same thing, it seems as though it only "triggers" when it goes through the system self test at like 15 MPH and only if giving it about 1/2 pedal or more. If I take off real easy and then at like 20 MPH give it hell it doesn't come on.

WTH! Is there any scan tool or anything that I can buy that will tell me what the codes its throwing are?

There are generic (~aftermarket) OBD scan tools that can read certains codes from your car. As far as I know no ABS codes though. The ones I've tried on my car were able to read engine (ECM) and transmission (TCM) codes only. Looks like only the Volvo Dealer can read all codes.

Well darn, yeah I have an ultra-gauge so I can pull engine codes, but my service light needs to be reset and the ABS read.