Boost problem,,,,,,,,

[Biggy]

please excuse my bad english.... but i really need your help!



The CAR:

UR-S4 2,2t
rs2 turbo
rs2 maf
rs2 injectors
rs2 cam sproket
7a cams
UR-S4 ECU modified into RS2 + T+S chip

everything worked excelent for more then half a year....

But now...



So THE SITUATION:

3000-4000 rpm on 2nd gear (for example).
pushing the gas pedal full throttle.
boost rises as always.
reving up to 7000 rpm.
shifting to the next gear.
pushing the gas pedal full throttle.
BUT! boost rises only to 0,9 bar (i have a stiff WG spring)

there are 3 ways of making it boost as always in this situation:
1) keep pushing the pedal. boost begin to rise as always in about 3 seconds.
2) let off the pedal and push it again.
3) shift MUCH slower (slower then you do in an everyday driving)

VAG-COM shows an error "Hall Sender -G40
Signal to positive Sporadic". this error shows up only in this situation. in other situations everything is fine. the car starts good.

no boost leaks, everything was fine.

what i did:
installed brand new original Hall sender and n75 valve.

everything remains - the g40 error and the boost trouble.



Any ideas?

[Biggy]

He-e-e-elp!!!!

[porkkis]

There could be something wrong with the TPS as boost control is TPS position dependant. Just a thought.

No idea about the G40 code. Double check the engine timing from bellhousing aperture.
Check G40 wires.

[Biggy]

There could be something wrong with the TPS as boost control is TPS position dependant. Just a thought.

No idea about the G40 code. Double check the engine timing from bellhousing aperture.
Check G40 wires.

thanx for idea.

Timing is tripple checked. g40 wires seem to be ok too.

i`m also thinking about checking pinging (detonation) sensors..

[Biggy]

any other opinions? your help is still needed!!!

[Biggy]

problem solved!

it was in the rs2 cam sproket. it was not broken but i changed it back to original aan one and everything works excelent now! no errors and full boost in any conditions!

the only question is why rs2 sproket worked fine for such a long period and only after a half a year it began to make problems and g40 errors...