Hi all,

I have a 1994 Villager with 197K miles. Out of the blue, there is now a thumping sound coming from the front left wheel when I brake between 10 and 35 mph. The sound is rhythmic (occurs roughly 2 times per second) and increases in intensity (volume) as speed decreases. The ABS (anti-lock brake system) light is not on. I have replaced the CV joints and boots, both front struts, had both rotors turned, replaced the brake shoes and calipers, and thoroughly bled the brake system. I have exchanged the rotors and front tires between the two front wheels to see if these were causing the problem, and the thumping noise still persists on the left front wheel. At this point, I guess the only remaining option is the ABS actuator pump (located on the passenger side under the hood between the headlight and the air conditioner dryer) since the pump has an individual output to each wheel, maybe the seal or piston output for the left front wheel in this ABS unit is worn out...Is this thumping noise a characteristic symptom of this particular ABS actuator pump starting to wear out/fail?

Has anyone had any experience replacing an ABS component? Just curious to hear some other DIY'ers feedback. I'd appreciate any ideas or suggestions.

Thanks,

This web page may help:http://www.mightyautoparts.com/pdf/articles/gb0805.pdf. I would remove ABS fuses to verify if that is causing the noise.

You have a bad rotor. Have the rotor turned again maybe at a diffrent place. The villager is very sensative when it comes to rotors. If you can just replace it. If you have a autozone buy it there since you can return it for any reason if its not. I am very sure that this is your problem since I had the same problem on mine years ago.

This web page may help:http://www.mightyautoparts.com/pdf/articles/gb0805.pdf. I would remove ABS fuses to verify if that is causing the noise.

dzus,
That's a great pdf. Thanks for the info. I did remove the ABS fuses, did a test drive, and the problem still persists.

You have a bad rotor. Have the rotor turned again maybe at a diffrent place. The villager is very sensative when it comes to rotors. If you can just replace it. If you have a autozone buy it there since you can return it for any reason if its not. I am very sure that this is your problem since I had the same problem on mine years ago.

IH8SPM,

Thanks for the idea. I purchased new rotors and had the old ones turned (they were still thick enough). With both the new and old rotors, the sound still occurs. I have also swapped the front rotors, but the sound still persists on the left front wheel.

It would seem you have ruled out a braking problem,may be a worn wheel hub/bearing.

It would seem you have ruled out a braking problem,may be a worn wheel hub/bearing.

That's what I am starting to think. Could the motor mounts be a possibility, due to the torquing of the engine as the vehicle slows down?

That's what I am starting to think. Could the motor mounts be a possibility, due to the torquing of the engine as the vehicle slows down?

I doubt it,bad engine mounts are most noticeable when accelerating from a stop.

Have you tried parking the van and jacking up both sides and doing a test with the wheels of the ground. It is really hard to pin point a sound when it in motion. The front bearing makes a whinning noise . WOW I just re read your thread and I had a another thought have you checked to make sure your brakes are mounted correctly? The villager has a sensor clip for wear that needs to be set on the outside of the caliper. I have had this problem as well. One more thing remove the rotor and check the bolts all five and the caliper bolts. Lube the caliper bolts if required but not the wheel bolts. The problem is in that area so tear down to the bare bone and re assemble.

I did jack the front end up and did a test to see if I could reproduce the sound. This was unsuccessful; I think the front wheels need to be loaded in the loaded condition. I also took apart each wheel down to the basic brake components. Re-assembled everything and the sound still persisted. So....I caved and went and got another brand new set of rotors. This fixed the problem.

Awhile back the rack and pinion (RAP) had to be replaced. The worn RAP had allowed the front wheels to become loose, i.e. you could move the front wheel in and out by hand when the vehicle was on jacks with the engine off. Prior to replacing the RAP, this "extra play" in the front wheels had caused both rotors to become slightly warped over time. Both the old and newer rotors I referred to earlier had been exposed to the old RAP "extra play". After getting another set of new rotors, all is well.

Thanks to everyone for all their suggestions, ideas, feedback. Hopefully this info helps someone out in the future. Best wishes to all my fellow home-garage mechanics.

ph919

Good thing you posted a result now others can use your key words to find this problem fixed.