Check engine light goes on around 3000rpm.
 

I got my car delivered at home today, when the rpms go to 3000 rpm the check engine light goes on, is this due to a bad mixture measured by the o2 sensor?

I'm pretty new to the supra and i have a lot of stuff to do to get it in good shape again.

Can you check your codes first please and get back to us after wards.

Sorry, only just started reading into the techmanual.
That SST wire can i solder one myself or should i go buy one?

And it seems to be above 4500-5000 rpm that it goes on, goes off when the ignition is turned off and afterwards only returns when i take the rpms high again.

I'll get back when i got the error codes pulled from the car.

sst, by that you mean paper clip right :P just stick a some wire or a paper clip inbetween terminals T1 and E1 of the diagnostics box by the main relay box and turn your car to the on position, count how many times the check engine light flashes, if there is a 1 second pause then the number continues, so example:

flash flash flash ... <1 sec pause>... flash flash flash flash
then your code equals out to 34, i think its 3 seconds of no flashing when the codes are done. but count 2 or 3 times just to make sure.

I get 5-2 which is supposed to be fault or open circuit in knock sensor signal.

The engine has been overhauled by the previous owner and they installed a metal head gasket and arp bolts, i'll try to find out where that sensor is located maybe they tore a cable.

As for the check engine on light at higher rpms, can this fault cause that?

I replaced the entire wiring according to the excellent guide i found here.
So it now has new connectors and a shielded cable wiring leading to the ecu.

The problem is still there.

well if the problem is still there i think that either its wired wrong, or the knock sensor itself is actually bad, gotta get that from toyota just get one and changem out to find out which one is bad

Knock sensors from the dealership are 350 bucks.