Audi 100 brakes - owen
I bought a cheap B reg (£200!) Audi 100 estate a couple of months ago, since we are renovating our house and it's handy for shifting materials and rubbish.

It's been fine since i bought it up until today. Driving home from work, the brake warning light came on. I stopped and checked the fluid level, and it was fine, so i carefully carried on home. Then, the brake pedal stiffened up considerably, so i needed to use all of my 17 stone to stand on the pedal to bring the car to a stop! However, this stiffness was intermittent, fine for one stop and a leg workout the next. To top it all off, the steering also became very heavy - this was also intermittent!

I have a feeling it may be the brake servo - any thoughts?

I am also completely baffled as to why the steering is affected? It had power steering, but surely the two systems are entirely separate?

Any help would be gratefully appreciated, as i don't want to spend too much on the car, but apart from todays drama it's far too good to go to the big scrapheap in the sky!
Audi 100 brakes - king arthur
Yep, it does sound like the brake servo. Did you check the level in the power steering reservoir? Probably just coincidence that these things happened together, they usually come in threes so expect one more thing to go wrong soon.
Audi 100 brakes - Richard Turpin
There is no brake servo on the Audi 100. The power assistance is provided by the hydraulic pump which also serves the power steering (and the self levelling rear suspension if fitted). I suggest your problem may be as simple as lack of fluid in the hydraulic system. You will have a (largish) plastic reservoir under the bonnet. From memory it\'s rear right (nearside). BEWARE to use only mineral oil to fill it as normal ATF ruins the seals. It\'s green and any Audi garage sells it. I believe Citroen among others also use it. There is supposed to be a warning light to show low level. Perhaps your warning light is broken.
If it\'s not low level, must be a problem with the pump. They are cheap 2nd hand and dead easy to fit as the pump is high up. Front right as you open the bonnet. (ie nearside front)
If the system leaks, it is probably from the steering rack, and will be worst on full lock. The racks are just over £100 recon but are difficult to fit.
Regards Richard.
Audi 100 brakes - owen
Cheers Richard, very helpful.

There is plenty of fluid in the reservoir, and the belt isn't slipping, so i'm going to change the pump this weekend. Found one at a scrappy for £35.

Like you say, it looks easy enough to fit, but I was just wondering if there is anything I need to know/do that isn't obvious, e.g. does the system need bleeding, and if so, how?

I know I should buy a Haynes manual, but at £15 it's 7.5% of the value of the car, and i'm just too tight! I'm keeping my eye out for a cheap one second-hand, but until then, any help is appreciated!

Thanks,
Owen
Audi 100 brakes - DavidHM
There are a couple of Haynes manuals on ebay for under a fiver.
Audi 100 brakes - owen
I know, i've just been looking, but I want to do it this weekend, and it'll take ages to get here by the time the auction finishes, and it's posted, etc.

Also, postage is expensive - i've just been bidding on one, went up to £3, but there was £3 P&P to add, and a couple of days left on the auction - i'll get myself to a car boot sale on sunday!
Audi 100 brakes - Soupytwist
If you want to use a Haynes over the weekend without buying one, that's what your local authority library is for.

They've defintely got one in Chelmsford library.
Matthew Kelly
No, not that one.
Audi 100 brakes - Richard Turpin
Last time I changed the pump there were no problems. I don't remember having to bleed it. It was very easy to change. say if you have difficulty.
Audi 100 brakes - owen
Richard - changed the pump this evening. Instead of intermittent braking and steering assistance, I now get NO assistance at all. Any suggestions?

Audi 100 brakes - M.M
Owen,

Air locked??

Try jacking up both sides together to raise the front wheels. Then turn from lock to lock time and time again untill no more air bubbles are seen in the fluid.

MM
Audi 100 brakes - owen
Cheers MM - i did do that last night, but I wasn't looking for air bubbles in the reservoir so maybe i didn't do it enough. I'll try it again over the weekend.
Audi 100 brakes - Richard Turpin
Owen,
Check the fluid is reaching the OUT side of the pump by turning the engine over with the OUT side pipe on the pump loose. If none, the delivery pipe must be obstructed. If it does it should be under pressure if the pump is OK.
Richard