Originally Posted by
cosy trav
Tabs The 5v on the pin to earth is when the iscv is unplugged , when its plugged im getting 12v on both sides to earth . Tried another valve and its still not working . Going to try and check the voltages pete posted and try both valves on my mates escos .
That sounds right mate, your seeing the earth side of the ISCV when connected hence the 12V and when disconnected you see the ECU power as described below, it controls the valve by PWM.
One things for sure the valves are FINE, it's rarely the valves that are the problem, it's the ECU's inability to control them correctly due to receiving duff info.
The reading is correct for 2WD the voltage DECREASES with throttle, however as you have L8 the voltage should INCREASE with throttle, this is the very reason for swapping the wires of the PF01 TPS when people fit L8 on a 2WD car, you have PF09 but in any case it should still read the other way, I.E voltage increasing with throttle, I feel pretty confident in saying this could well be your problem.
Martin