traction control issue fully closes throttle

[gtpornstar]

Trouble shooting in my mates aristo
2jzgte with r154 conversion, has a vvti late model motor and i think no map sensor, but has afm.

when he hits full boost the car violently cuts off and i believe the traction control flap completely closes, because the accelerator pedal doesnt work (any movement in the throttle doesnt increase revs), at this point the engine doesnt shut off but just idles.

No traction control light comes on but engine check light comes on and codes shown are 41,51,7 and 8.

from the net i got this

7and 41-THROTTLE POSITION SENSOR SIGNAL--OPEN OR SHORT IN TPS SIGNAL
8-INTAKE AIR TEMPERATURE SENSOR SIGNAL--OPEN OR SHORT IN
51 - SWITCH SIGNALS - IDL (tps) CONTACTS OFF, NEUTRAL START SWITCH OFF, A/C SWITCH "ON" SIGNAL TO ECU

checked all the wiring and it seems fine, nothing unpluged no split wires etc.

car was running fine, then was parked up for a while and now has this issue.

[RS13]

Find the voltage readings for the TPS, grab a multimeter and test it. How much boost is he running?

[MrOizo]

You have the 2nd throttle dont you?

just take it out

[johndoe1025]

you can disconnect the TRC throttle im sure?

[gtpornstar]

RS13 - test the voltage at idle or on boost ? running 1.3 bar boost.
Mroizo and John - yeah i know it can be disconnected but he is more worried about why it is happening so that nothing blows etc.

[MrOizo]

i think its something to do with a speed sensor.
It should have ABS. maybe it detects no speed some where.
I remember Gadget had this problem when on the dyno.

re-read your post and dont think its the same... hmmmm...

[johndoe1025]

id be checking that the TPS and AFM are working correctly, check them with an ohm meter? outta my depth tho haha

[gtpornstar]

one thing i am leaning towards is the wiring under the dash

[ChaosAD]

If you think it may be the wiring check its not a dodgy earth

NOTE: sensor earths go back to the ecu so wont be earthed with the ecu removed