Hello folks,

I'm new around here and seriously hoping someone out there can help me out with this.

My wife drives a '04 Tribute that has been a fantastic car for us. Recently, however, we've been experiencing a weird issue with the brakes. We've been to a dealership and a CarX and no one can tell us what's going on. Here's the best I can describe the issue:

Typically on the first brake of the day after getting up to, at least, 40 mph, the car stutters as it brakes. It almost feels like the ABS kicks in erroneously, but the sound isn't quite right to convince me that it's the ABS.

We've been assured that whatever the problem is, the car is safe to drive. However, this morning the car actually died immediately after/during the stuttering occurred.

I'm really hoping someone out there has had this issue, was able to track it down, and can tell me what's going on here. As I said, our dealership is claiming that nothing is wrong with the car.

 

I need clarity on the stuttering.
Is the engine stuttering or the brakes or suspension.

I personally had issues where I had a lean code and my power brakes intermittantly were gone.
I had an internal vaccuum leak in the brake booster which caused the engine to run rough when the brakes were applied.

They found it by looking at the computer data with the brake booster vaccuum line pinched off with a pair of vise grips against not pinched off while brake pedal depressed.

Otherwise, good luck.

 

I can't be sure of this but I think it is worth checking.
The ABS relies on the wheel speed sensors (ABS sensors) for input. They are pointed to a toothed ring (tone ring) at the hub. You could clean each sensor and make sure it is at the correct distance to the tone wheel. Also check each wheel for worn bearings. If the hub has any play it could affect the sensors' ability to read the tone wheel.

 

I'll preface this with a disclaimer of 'I know very little about cars.' It feels like it's the brakes. It feels like the pads are skipping or slipping as they try to grip the disc, but catching every quarter second or so. The braking is still effective, but does feel like it's slowing down a touch slower than it normally does.

I can't figure out why this would only happen once, though. As I said, it's always the first brake of the day, after getting up to speed. After that, we never feel the issue until it sits overnight.

It sounds like, though, I should make sure that the dealership looks into the computer as well as everything else they might do?

During our initial research into this issue, we saw this suggested somewhere. I don't know how to do this myself, but we mentioned it to the dealership and they seemed confident that it wasn't the issue. I'm not saying I necessarily take them at their word, they didn't seem like they were too interested in the idea when I mentioned it, but I have brought it up to a mechanic.

 

I am left to guess what could cause this single occurrence after a rest period.
Our Ford Contour's ABS does a self test at the first time it reaches like 10mph. It makes a 2 or 3 second long buzz. I don't know if your vehicle has such self test feature. Anyway I can't imagine that it should be happening at 40 mph.

It is likely that they paid attention to the wheel bearings and the sensors while they took the wheels off.

Most ABS systems require a specific bleeding procedure to get the old fluid and air bubble s out of the pump. I would ask them how much it costs to replace the fluid and bleed the abs. That way you don't tell them anything...

Mechanics don't like to be told anything because they think they know everything.

Also, I would stay away from the CarX man and the other franchise shops. I would look for an independent shop, something like "Ron's Automotive". Ask friends who is good in your area.

 

Remove the ABS fuse &/or relay. Your standard braking will still work. Go for a drive and see if it plays up.

I've had a tribute with a cracked ABS ring before causing all sorts of weird issues.

Also I've had to replace a few brake boosters on these before too.