I have 2001 Isuzu Trooper that was driven through mud puddles over the headlights several times. The Trooper made it home with no problems and the engine was rinsed off. It sat for a day and now it will start and run well for 3 seconds and then quit. It has been in this condition for 3 months.

Parts that have been replaced without success.

ECU module
Throttle body/position sensor
misfire sensor
Mass Air Flow
Fuel Filter
Starter
Battery

Ignition and fuel pressure are good.

Codes that displayed are
1290
1299
1295
1515

Codes have been cleared and the engine will not run long enough to generate new ones.

The Reduced Power lamp illuminated when the engine is running.

Any advice is appreciated.

Thanks.