ABS - Intermittent
#1
Racer
Thread Starter
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Hi
I'm new to this forum and new to 964s, so hello!
I got my 964 end of Feb this year and am enjoying it
However, I seem to have an ABS problem. I've tried a few forum searches but can't seem to find ABS problems the same as mine, so here goes:
My ABS works intermittently!
Generally, if testing it either doesn't work at all or it works for the first one or two tests and then won't work.
The wheels lock up and it goes into a slide - I'm assuming the ABS should kick in at this point!? This has got me into a bit of bother, so am keen to fix it!
I have no warning lights to suggest there is a problem.
It's just been a through a full service and no faults show up on the diagnostics.
I've had the ABS relay replaced.
The control unit has been tested on another car and is OK.
I'm told the sensors look like they could do with being replaced - but why would it work and not work? Is there any way of testing the sensors for sure before buying new ones to no avail?
So, can anyone shed any light/point me in any direction?
Cheers
Scott
I'm new to this forum and new to 964s, so hello!
I got my 964 end of Feb this year and am enjoying it
![thumbup](https://rennlist.com/forums/graemlins/thumbup.gif)
However, I seem to have an ABS problem. I've tried a few forum searches but can't seem to find ABS problems the same as mine, so here goes:
My ABS works intermittently!
Generally, if testing it either doesn't work at all or it works for the first one or two tests and then won't work.
The wheels lock up and it goes into a slide - I'm assuming the ABS should kick in at this point!? This has got me into a bit of bother, so am keen to fix it!
I have no warning lights to suggest there is a problem.
It's just been a through a full service and no faults show up on the diagnostics.
I've had the ABS relay replaced.
The control unit has been tested on another car and is OK.
I'm told the sensors look like they could do with being replaced - but why would it work and not work? Is there any way of testing the sensors for sure before buying new ones to no avail?
So, can anyone shed any light/point me in any direction?
Cheers
Scott
#2
Rennlist Member
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Kent,
Do you have a C2 or a C4?
Ricardo
Do you have a C2 or a C4?
Ricardo
#3
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Having bad sensor probably will show up on a diagnosis. Having dirty sensors might not unless the car is rolling.
I've pulled my sensors and had about 0.5 cc of metal filings on the ends of the magnets.. Cleaned them with a Qtip; it's a free inspection. Give it a shot.
I've pulled my sensors and had about 0.5 cc of metal filings on the ends of the magnets.. Cleaned them with a Qtip; it's a free inspection. Give it a shot.
#5
Racer
Thread Starter
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Originally Posted by colo964
Having bad sensor probably will show up on a diagnosis. Having dirty sensors might not unless the car is rolling.
I've pulled my sensors and had about 0.5 cc of metal filings on the ends of the magnets.. Cleaned them with a Qtip; it's a free inspection. Give it a shot.
I've pulled my sensors and had about 0.5 cc of metal filings on the ends of the magnets.. Cleaned them with a Qtip; it's a free inspection. Give it a shot.
#6
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They're held in by a small hex headed (Allen?) bolt. There are usually only two possible problems removing them:-
1. The head of the bolt corrodes so your Allen key won't fit (pass the Dremel and replace with an ordinary bolt)
2. The sensor is corroded into the housing.
If you're going to take them out, give them a good dose of penetrating fluid a few days before. While you're in there, check that the teeth are all stiil there on the ring around the cv joint. If you measure the resistance of the sensor, it should be in the range 800-1200 ohms. Use some copper grease when you refit them.
1. The head of the bolt corrodes so your Allen key won't fit (pass the Dremel and replace with an ordinary bolt)
2. The sensor is corroded into the housing.
If you're going to take them out, give them a good dose of penetrating fluid a few days before. While you're in there, check that the teeth are all stiil there on the ring around the cv joint. If you measure the resistance of the sensor, it should be in the range 800-1200 ohms. Use some copper grease when you refit them.