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Discussion Starter · #1 ·
Hi all
Just bought my 6th saab. A ropey 4 door 2.3fpt auto. There are various issues requiring my attention. BUt - this is the most important.

I noticed the brake lights were permanently lit. It turns out the front brakers are binding. Initially I guessed calipers. However Im having to lift the brake pedal slightly as it doesnt return fully when I take my foot off the brake.

Even doing this doesnt lift the 'thingy' ( plunger end? Is this the back end of the master cylinder that pokes thru the pass side of the bulkhead? ) suficiently to push in the brake light switch on the passenger side. Subsequently the brake lights remain lit.

Now Im no genius but Im guessing partilly seized calipers aren't going to cause this. Am I looking at an acumlator or master cylinder problem?
The brake fluid is very dark and ancient looking.
When I've pulled the pedal up as far as I can ( brake light still lit -brake light switch not pushed in completely ) the car will move off in DRIVE without any gas.

Any help would be greatly appreciated!
Paul
 

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What year? The first generation ATE ABS brakes suffered from failed Master Cylinders which is a big problem due to the cost and lack of availability.

While there is some push back from the rotors pushing the pads against the caliper pistons there is also a return spring on the brake pedal and a return spring inside the main cylinder of the Master cylinder (the first generation ATE MC used an automatic cylinder to pressurize the rear brake lines. The pedal only acted directly on the front brake lines.
 

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Bad news. You have the troublesome early ATE ABS. Probably your MC is in need of replacement. Hard to find and expensive.

I always wonder why owners fail to observe the 2-3 year (depending on ambient humidity) required service interval for flushing the brake fluid. It is cheap and absolutely essential.

I do this on all my cars. The only brake failures I have had resulted from external corrosion of caliper pins, never any internal issues. I have also only replaced one Master Cylinder (twice) on my Alfa Romeo, never on any other car.
 

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Discussion Starter · #5 ·
Thanks for the good news!!
Didnt pay very much and it is only a stop gap as Im hoping my other half is going to treat me to an Aero very soon! The muppet who sold me the car ( well, perhaps I was the muppet! ) would've struggled with his shoelaces never mind changing the brake fluid...
The car is driveable. I have to remember to stick my foot under and give the pedal a little lift - not so bad as its an auto. I did intend changing the fluid this weekend and checking the calipers any way - would I be wasting my time?
 

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Now I realize I am familiar only with North American spec cars. Maybe your Euro spec doesn't have ABS?

It certainly would be worth trying a brake fluid flush.

Normally, failure of the MC would trigger the ABS fault light. If there is no fault light then maybe you just need the brake fluid replaced.
 

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Discussion Starter · #7 ·
flushed!

Thanks for your continued interest Superaero. I could be wrong but I think most 1990+ 9000 have ABS in the UK.
Flushed the brake fluid at the weekend. Old fluid looked pretty healthy though. Stripped the front calipers whilst I was at it. copper greased the sliders, etc, etc. Took the car out yesterday - no change. The ABS light does take a little longer to go out though...hehehe - just my luck?!...

However - I've just removed the clevis pin from the the brake pedal assembly and master cylinder fork. Now as its RHD, my car has a bar that runs at the back of the dash, over to the left hand side - so obviously differs to LHD variants.

Can someone tell me - once Ive removed this clevis pin, should the brake pedal drop to the floor & swing freely without any resistance? Its just that there is a spring fitted to the left hand side bracket which on my car appears to do nothing?

I'm clutching at straws here - but Im wondering if this iis the cause of my brake-binding issues....

Any help from anyone would be hugely appreciated!!
 
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