ABS braking weirdness on 2010 LT
04-13-2021, 04:30 PM
#1
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Join Date: 11-20-2011
Location: Pulpwood Holler, extreme NE GA
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ABS braking weirdness on 2010 LT
Let me state first I installed SS rotors and Green Stuff pads several years ago and never had a problem until recently. The weirdness began with braking hard during a transition from a smooth to a rough surface. The ABS kicks in and pedal seems to 'drop' considerably. First happened on a cold day back in Feb. Brake pedal remained mushy and low for about an hour then returned to almost normal and stayed that way until today. I say almost normal but it seemed a bit mushier than it had been for the last 4 years. Then today exact same thing happened-I was braking hard and went from smooth pavement to some unexpected rough cobblestone and felt the ABS kick in and the pedal seemed to go almost to the floor! Both times I was braking hard while making a right turn if that matters. Also, today the ambient temp was about 80 degrees F. From then on, pedal was mushy and seemed to go down much further than normal but the system would still brake well, it just took much more effort and much more pedal. We then had to drive over a mountain whilst it was doing this (oh yes, that was lots o' fun!). Stayed this way for nearly an hour over about 35-40 miles. Then, after reaching the base on the far side of the mountain, the pedal suddenly seemed to return to normal. Of course, by then we were nearly home. The vehicle has 131K and has no lights on dash other than check engine light (code says crankshaft position sensor-but it's been on for several months) and brake fluid reservoir checked full. Front brake pads were checked after the first occurrence and found to be @ 50%. Does the ABS system have to 'reset' it's self after a hard use? And should it take an hour or so and driving 30-40 miles to do it? Any other ideas or is this 'normal' and I have to live with it? While it is worrisome to me when it happens, I can deal with it as long as the brakes will still work until it returns to normal but-the wife will freak out if it ever happens to her...
04-13-2021, 07:02 PM
#2
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Join Date: 10-13-2011
Location: Welland,Ont Canada
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It could be the 11 year old brake fluid, unless you have flushed it out .
It could be the flex hoses are getting mushy, they are also 11 years old, unless you have changed them.
exactly what code does your OBDII port report ?
It could be the flex hoses are getting mushy, they are also 11 years old, unless you have changed them.
exactly what code does your OBDII port report ?
04-13-2021, 08:16 PM
#3
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Join Date: 01-23-2009
Location: Fredericksburg,VA
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Explanation for the first part is when you stomp on the brakes on an uneven surface the wheel speed sensors sense the wheels spinning at different speeds.
Possible explanation for the second part is you perception of 50% wear may be incorrect. If the groove is nearly gone it is time to replace.
Or, the activation caused some sort of hydraulic overload in the system and all of the rubber hoses inflated and softened.
I am assuming you have been paying attention to the rear adjustment.
Possible explanation for the second part is you perception of 50% wear may be incorrect. If the groove is nearly gone it is time to replace.
Or, the activation caused some sort of hydraulic overload in the system and all of the rubber hoses inflated and softened.
I am assuming you have been paying attention to the rear adjustment.
04-14-2021, 05:20 PM
#4
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Join Date: 11-20-2011
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OldBlue-but wouldn't either condition cause the problem to remain constant after beginning?
I had stopped by an Autozone-they handed me a small handheld device and told me where to plug it in. Did so and took it back in and the parts monkey said it was either crankshaft position sensor or camshaft position sensor. It's been a few weeks since but it was one or the other. Oh and get this, whilst running errands today, the check engine light went off in between stops. Of course, it came back on with the next restart-GRRR!
bad news-I stopped by the most rec'd mechanic (I live in a rather rural area) and was told he is booked solid for six weeks! Says he is working until midnight most every night-and he is by himself and he can't buy any help at any price! He looked rather puzzled tho when I mentioned the code. He then remarked that these engines aren't really known for that problem. I'm hoping it may be a corroded sensor connection.
Don- the overload situation sounds like what is happening but then again, I ain't no mechanic. I'll be sure and check out both pads and shoes when I replace the brake fluid.
I had stopped by an Autozone-they handed me a small handheld device and told me where to plug it in. Did so and took it back in and the parts monkey said it was either crankshaft position sensor or camshaft position sensor. It's been a few weeks since but it was one or the other. Oh and get this, whilst running errands today, the check engine light went off in between stops. Of course, it came back on with the next restart-GRRR!
bad news-I stopped by the most rec'd mechanic (I live in a rather rural area) and was told he is booked solid for six weeks! Says he is working until midnight most every night-and he is by himself and he can't buy any help at any price! He looked rather puzzled tho when I mentioned the code. He then remarked that these engines aren't really known for that problem. I'm hoping it may be a corroded sensor connection.
Don- the overload situation sounds like what is happening but then again, I ain't no mechanic. I'll be sure and check out both pads and shoes when I replace the brake fluid.
04-14-2021, 07:01 PM
#6
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Join Date: 10-13-2011
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Either condition should be constant, however the abs computer will try to compensate.
so , don’t trust the parts guy, about the code. Get someone to read the code and write it down, not what they think it means crankshaft position code and camshaft position codes are different, and usually are not the sensor causing the code, dirt , corrosion and loose connections are usually the cause
so , don’t trust the parts guy, about the code. Get someone to read the code and write it down, not what they think it means crankshaft position code and camshaft position codes are different, and usually are not the sensor causing the code, dirt , corrosion and loose connections are usually the cause
04-15-2021, 08:34 AM
#7
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"either crankshaft sensor or camshaft sensor"= lazy mechanic that does not want to change the timing chain. Why blame innocent coils of wire embedded in epoxe when the are just doing their jobs?
If you have that code your ABS is turned off. Explains that.
If you have that code your ABS is turned off. Explains that.
04-16-2021, 11:32 PM
#8
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Join Date: 11-20-2011
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Old-not many shops around these parts.
Don-the only mechanic involved did not look at my car. He was far too busy and can't even buy any help at any price.
Once again-this is a very rural area and not many repair shops worth bothering with is available. Between the coof and all the "free money" available, nobody is willing to work...
FWIW, the Autozone here is the smallest one I've ever been in and that was only the one time.
Don-the only mechanic involved did not look at my car. He was far too busy and can't even buy any help at any price.
Once again-this is a very rural area and not many repair shops worth bothering with is available. Between the coof and all the "free money" available, nobody is willing to work...
FWIW, the Autozone here is the smallest one I've ever been in and that was only the one time.
