Toyota Nadia SXN10 E/G Stalls

1999 Toyota Nadia SXN10 Engine Model 3S

Situation
The engine stalled at an idle.

Cause
Faulty ECU ( computer)

Maintenance
Carbon sludge were piled up by exhaust gas recirculation system.
I cleaned ECU, but it did not work well.
Then I exchaged new ECU ( computer).