Brake pedal flutter...abs light on (1 Viewer)

[HardyDanger]

Expeincing an abs issue on a 97.

Here's the scenario.

Stopping from about 20mph, My brake pedal initially has what feels like higher resistance than normal, but flutters a bit and doesn't seem to really want to stop the rig, then it goes away with more foot pressure and works as normal.

That happens for 2-3 stops. Then ABS light comes on for the rest of the drive and the fluttering/weirdness is gone. And stops as normal. Any thoughts?

I tried this 3 times. Taking the key out starts the cycle over.

I'm gonna try to pull the Abs fuse and see what's different for the drive home.

Ironically, was just reading the abs delete threads last night. Better becareful what I read next!

This weekend will try the blinky light FSM diagnostic listed on other threads.

Thanks.

 

[on3i11s]

By flutter, do you mean a kind of pulsating sensation in the brake pedal, because that's what I have happening occasionally right now with my '97 also. Not a major problem, but is definitely noticeable when it occurs.

I'm currently dealing with a loose caliper bolt issue so I'm not sure if that plays any role in this. New brake pads, rotors, calipers, hoses, fluid, tires, and a recent axle rebuild so I'm leaning more so towards the ABS sensor or something. My ABS light does not ever come on at all, even when locking center diff.

Here's a thread from the FAQ if you haven't seen this one yet:
Cleaning ABS sensor magnets

 

[HardyDanger]

thanks on3i11s
was just reading that faq too. Will be trying that after I pull the blinky codes.

it's def a pulsey/flutter, crunchy kinda thing. Like biting into a live fish, only its stepping the brake pedal. It feels like what you'd expect when you stomp the brakes on dirt road and the abs engages, except that the pulsing occurs on dry road, a medium pedal pressure.

 

[HardyDanger]

pulled the codes.
got two.
1-1
3-3
Yahtzee!!!

Next stop rear right rear wheel.
Assume the 1-1 is from pulling the fuse?

 

[on3i11s]

Glad you gained some info on your ABS problem, can you link to the threads with the "blinky light" diagnostic codes and procedures. Good luck!

 

[madisonr34]

Remove your ABS sensors on each wheel and clean them with a damp cloth. Most likely a dirty sensor tripping off the ABS system.

 

[cartercd]

I fought the same issue. In my case an ABS harness wire had been spliced, which apparently altered the signal from the sensor enough that it would occasionally cause the symptoms you described. I found a partial ABS harness in the mud classifieds and my problem was solved. Check the sensors first, then inspect your harness.

 

[HardyDanger]

I ended using the Haynes Manual instructions for diagnosing the abs. (Mainly because my digital copy of FSM was, well digital and Haynes is also written for bananas like me.).

That said, the hardest part was finding a paper clip for the jumper.

Next weekend will start cleaning the sensors 1 by 1 and or inspecting harness. (And hopefully installing CDL switch).

Pics.
Haynes page. And the diagnostic box with paper clip (located on the RH side of firewall right below wiper motor.)

 

[HardyDanger]

Results.
The RR Abs sensor was dirty and had about a 1/4" of goo stuck to the tip. All clean.

Victory. Popped the ABS fuse back in and, boom. ABS is back online working perfectly.

bUT wait.

THEN. Went to clean the fronts, for the love on PM, but the bananas at BIGO seemed to have welded my lug nuts to the hub went they put on my new front sneakers two weeks ago.

I can't crack them with any reasonable amount of force Evan with my 36" x 3\4" breaker bar. And worried they are going to shear off. Both rears popped right off.
Or should I just lean on that breaker and see what happens.

So. Going back to big o to make them do it, so they can shear them off and the blame me. $&#%!!

Nice and clean abs sensor. Couldn't even see the tip was white when I pulled it out.