Only noticed this since fitting the S8 Syvecs but under acceleration I get a Brake Distribution Warning and PSM and ABS malfunction, I thought this was due to attempted wheelspin but now not so sure, in trying to get wheelspin and flooring it to induce between corners I notice the brake pedal goes solid as well (it has new venturi valve and a replacement one way valve at servo) if I kept accelerating the pedal would be normal after a second or so, this is when doing real point and squirt stuff. Ive pressurized the system and there are no boost leaks or boost trying to go up to the servo.
Im running 315/30/18 and 234/40/18 but never saw this warning with the DME, any ideas before I pull the S8 and try the DME back in?
Strange thing is after a while I can drive the car as hard as I like and the warnings dont come up !!!!

 

I know the EMS has some input to ABS, any other warning lights? Early video of the ProEFI test car that Jason shot has the dash lit up pretty good including all sorts of ABS warnings! You should be able to check the sensors via the Syveccs at least. Probably something just a little off in the settings. We need an EMS forum ;-)

 

check for vacuum/boost leaks seen some strange brake issues with that before

 

OK guys I have a theory, googling this and a few guys have had it with oversize tyres, when i fitted the Syvecs I also swapped my track day tyres back to my road tyres, they are near their limit, I think they are low enough on tread to confuse the computers controlling PSM and ABS, I am going to swap back and try that.

 

Done that, the system holds 15psi no problem

 

I'm somewhat sure that the PSM is being fed data from the ECU, less sure about ABS. The ECU will know about tire height I think and certainly monitors wheel speeds for its traction control. You might want to look over the settings or perhaps contact whoever set it up and see if you've got an issue there.

Curious, does anyone know if the speedo is on the CAN bus and also controlled by the ECU?

 

Forgot to mention I put the DME back in and it does the same thing. I changed the rear tyres when the syvecs went in as i didnt want to destroy my track tyres on the dyno.