[928NZ]

Hi Guys

I have an on going problem with my 1990 Porsche 944 Turbo ABS system.

I am selling the car and would like to fix the problem before it goes to a new owner.

ABS sets up correctly on start up –

I move forward and it fails the self test at 4 mph.

I have rigged a switch to the fuse and can turn the ABS on or off.

I turn it off – accelerated hard and switch it back on – ABS sets up beautifully.
It will not reset at anything but hard acceleration.

Until the next time I stop where it fails the next self test when starting off.
It sounds like a bad earth problem which is overcome when I accelerate hard.

Checked and re cleaned every earth I could find

Perhaps it is caused by one of the two relays on the ABS pump?

I booked it into the Porsche dealer a couple of years ago and they said that it was the right rear ABS cable, so I ordered one but the ABS failed immediately on start up.

Funny thing was when I collected the car it setup beautifully and only failed again when I was a mile or two away.

Hoping someone has a clue.