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Rich idle, fine on cruising

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New to here and need some help.

All stock glanza having this problem with running rich on idle and fine on part throttle and cruising.

Idles fine, starts at 1200rpm when cold and then moves down to 800-900rpm but lambda sensor reads 0.8 - 0.9v. At cruising and part throttle reads 0.3 - 0.8v which I think is fine. 

Checked TPS voltages at Ecu pinouts


PSW - 5v on idle and part throttle

PSW - Ov on WOT


VCC always 5v


IDLE - 0v on idle

IDLE - 12v on part throttle and WOT (maybe floating voltage?)


Map sensor 2.6v with engine off

IAT 0.8v with engine off

Coolant sensor 0.4v (car has been resting for 20min)


Looking up resistance tables for tempreture sensors, iat and coolant sensor seem fine. 


What could be the issue please? Thanks 


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Ifs its standard ecu it should run rich when cold and lean out after its fully warmed up. Thats what mine does. 

Also found when disconnecting battery it would take time to for it to get back to normal. 

A wideband air fuel ratio gauge is what you need.


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