Can a defective hall sensor or CPS cause boost cut off?

[Jonas_R]

While we where mapping the car last sunday the hall sensor suddenly started to throw an error code saying something about Hall sensor shortend to B+.

However the fault code only came up when above 5000 RPM and at WOT. We actually had to stop since we could not resolve the problem.

Now at first we thought that it would be a defective hall sensor, however it is fairly new and the code only cam at high revs and WOT. So we thought that perhaps it could be the Cambelt sprocket that was starting to go bad, and thereby making the timing just a little bit off.

But after reading on s2central.net i'm unsure if the hall sensor even have the capabilty of doing this? Perhaps I should be looking at G4 the crank position sensor?

Anyhow I'm doing the cambelt change since it is around that time, and will fit a machined cambelt sprocket. But any suggestions will be good.

3B with RS2 setup converted to multi coil setup using AAN ECU and 034 high output coils.

[Billman]

I think i read somewhere that with a faulty hall sensor the engine is working ok will some RPM and them it jumps to safe mode.

[UrS4boy]

Anyhow I'm doing the cambelt change since it is around that time, and will fit a machined cambelt sprocket. But any suggestions will be good.

3B with RS2 setup converted to multi coil setup using AAN ECU and 034 high output coils.

Remember that the cam sprocket has the inner "tin" timing ring that runs through the CPS Hall sender. Also, if I remember correctly, I think Mihnea once noted that at anything above 4000 RPM, the Hall sender isn't involved with all timing requirements taken by the G4 crank position sender. Here is some G4 info:
http://forums.audiworld.com/s4s6/msgs/116988.phtml

[Jonas_R]

Hmmm but what will the hall sender shut down boost if the cam sprocket is sliding in the key? or is the crank position sensor that will do this?

[ifa]

If hall signal is missing boost and knockcontrol are disabled. Ignition timing is also retarded.

[Jonnybravo]

My S2 will occasionally misfire, sometimes on full load, other times when its just idling it will pop and nearly cut out.

We thought it was boost cut but its too random for that, I have occasionally ended up with under a bar on full boost though then it will sort itself out.

CPS common fault on the S2's ?

[ifa]

Quite common especially when hall sensor is original.

[Jonnybravo]

I best get one sorted then, cheers

[stus2]

hi lads sorry to butt in ur convo im havin a simular prob , where and how much can i get a crank position sensor..... i need one today as need to use my car tommoro so ur help woll be much appreciated

[A80Avant]

not sure if it helps but i have had the hall sender fault code whenever i reached the rev limiter on my car

[AUDIS2avant]

stus2 : have you tried quattrocorner?
He´s quite helpfull, just give him a call