1993 surf 3.0 1kzTe manual - engine warning light

[Robert Scott]

Engine warning light illuminates when coasting about 1700rpm or lower. Solenoid or relay is herd to click and power from Turbo declines. Resets If engines turned off. New head, Radiator, 3" exhaust, waterpump, thermostat. Sensor?

Does anyone have suggestions on most likely cause. When testing for fault codes in accordance with manual, no fault codes. Also 'no fault code' does not occour. Seems like diagnostic test plug not working. Thankyou for your thoughts on the matter.

[Robert Scott]

 I am Looking for possible faulty sensors. 

1. Air flow sensor on inlet Manifold.. 

2.Throttle position sensor on Throttle body.

3. Crank position sensor on block.

I think these are possible causes.  I have cleaned contacts, made sure air flow sensor connection port is not blocked.

Injector pump has been fully reconditioned.

Has anyone one experienced a similar problem and found a faulty sensor was a cause of intermittant power loss?

 

[flash22]

Can you talk to the ecu and get live data ? Sounds like an over boost cut or map sensor issue