Hello, new to the site and unfortunately came with a problem. My Z is doing a pulsation with the ABS pump "BUZZ" whenever your coasting down to a stop (obviously brakes applied). It does about 3 to 4 pumps and then your at a full stop. I've changed the rotors, pads, brake fluid, and even swapped wheels thinking maybe its the tire difference. I used a friends diagnostic tool and only hint I got was that there was low voltage to the ABS computer. I believe it was DTC C1109. Question is should I look into the ABS module under the steering column or think about changing the complete ABS unit??? I took it to different places and still cant figure it out. Nissan said it was the steering angle sensor and we got into an argument about that so they are just going by a manual.

 

Welcome- it helps to know what year and how many miles are on your Z when asking questions like this. Did this brake problem start recently, or has it always been there?

 

Sorry, 2003 Nissan 350z with 124k miles, brembo brakes, and I just got the car. However i can say the car was neglected by the previous owner and had things that needed to be taken care of.

 

Since the car was neglected by the previous owner, have you changed all the fluids yet? Besides engine oil/filter, tranny, diff, etc. the easiest place to start is to do a four wheel brake flush with high quality DOT 4 brake fluid. Make sure you get ALL the air out of the system to eliminate that as a possibility.

 

Yes, did that first thing also set the steering angle sensor back to zero thinking that was it. I’m almost leaning towards the computer for ABS or the whole module itself. It’s driving me insane. I pulled the ABS relay and it stopped.

 

For this condition I highly doubt it’s a fluid issue, or even a braking issue. To me this sounds like a wheel speed sensor dropping off, which happens at low speeds because at higher speeds the sensors are easier to read. What I would do (if you’re mechanically inclined) is remove each wheel speed sensor and inspect the tone ring/reluctor wheel for any damage or teeth/chunks missing while turning the wheel bearing/hub flange slowly. If they all look good and the sensors look good as well you’ll need to find a scanner that can monitor live wheel speed, then perform a slow stop or two and check to see which one is dropping off (losing speed suddenly).

 

can you get a replacement reluctor or is that built into the hub? I think on the rear end its on the differential right?

 

Its on the inner flange I thought, which you should be able to see very easily…..take a close look while rotating and you may see a crack in the ring, Fords are famous for this issue of cracking. I’ve never changed a ring on a Nissan, but have tried on a Ford and it’s a tough thing to do, the ring is very brittle and snaps easily, you’re probably best off to get a new flange if that’s the issue you find.