Contour Enthusiasts Group Archives Forums General Troubleshooting Problem with ABS

Hey all!

I am having a problem with my ABS. It seemed to start after I changed my stock 215/50s for 225/50 on the rear end. After that usually when I hit the brakes I can feel the abs pulsate under my feet. I am wondering if this has to do with the speed sensors registering different speeds and engaging the abs prematurely. I am hoping this will be fixed by new tires up front.

Anyone have anything else to say about it?

- Mike

is your front size different then you back?

i think thats bad.

doesn't abs determine slipping by measuring wheel speed?

[edit] oh wait, thats what your asking....never mind :rolleyes: [/edit]

Yes, they are different, my fronts are stock and my rear is one size bigger.

I am hoping if I get the same size on the front (one size bigger than stock) it will cure it.

You must have the same diameter wheels front and back, or the ABS will not work properly, it will think the larger diameter wheels are slipping, and try to correct it, which is not possible.

I believe you meant to say sliding (ie lock-up).

With traction control the opposite, i.e., system would think small tired wheels are slipping (spinning) since they would be doing higher rpm.

You might have a problem from the different tire size, but I have know others to have the same setup you do with no adverse effect. I would also make sure that the lug nuts are torqued properly. You may be feeling warped rotors.

I have had a problem for a year now that seems very similar to yours yet I have the same size tires front and rear.
Whenever I come to a slow stop the abs cycles and I can feel it in the pedal as well as hear it cycling under the dash. No ABS light comes on though. So I dont think there would be an error code.
I purchased a new front sensor an have yet to swap them out. I thought about disconecting it altogether.
I hope to get around to troubleshooting some day but if you figure it out or if anyone has any ideas then please share.

Thanks,

I am pretty sure that the pedal feel does not feel like discs being warped. I am hoping that my new tires will halp this (which I need asap because my current front tires are down to the fabric on the inside).

My father mentioned that Ford may have to reset the computer for a different final drive ratio. I know my tach is about 1% off becasue of this, which I am not too concerned about, but would that be possible/ help anything?

And do we have an electronic speedo or a cable system?

Thanks - Mike