LIMP MODE WOTH NO CODES AND PERFECT ECU

[Alin.skrillex]

I own a ls400 from 1996.

i bought the car a year ago, after I bought it I’ve drove the car for 2weeks with absolutely 0 issues. And then while I was driving the car all of the sudden the car lost the power , never had the check engine light on, I’ve checked for the codes and I had only the oxigen sensors codes…. Which obviously I’ve replaced them and then I got rid of the codes but the car is still in limp mode ( I’ve replaced many more in that time and I checked the ecu and is perfect condition) anyone knows what to do?!??????? 
 

 

ps 200k miles 

[RX400h]

On 12/11/2024 at 5:22 PM, Alin.skrillex said:

I own a ls400 from 1996.

i bought the car a year ago, after I bought it I’ve drove the car for 2weeks with absolutely 0 issues. And then while I was driving the car all of the sudden the car lost the power , never had the check engine light on, I’ve checked for the codes and I had only the oxigen sensors codes…. Which obviously I’ve replaced them and then I got rid of the codes but the car is still in limp mode ( I’ve replaced many more in that time and I checked the ecu and is perfect condition) anyone knows what to do?!??????? 
 

 

ps 200k miles 

CoPilot response:

Quote

Since you've already replaced the oxygen sensors and checked the ECU, there are a few other potential causes for the limp mode issue:

1. Throttle Position Sensor (TPS): A failing TPS can cause the car to go into limp mode. Testing and replacing this sensor might help.

2. Pedal Position Sensor (PPS): Similar to the TPS, a faulty PPS can trigger limp mode.

3. Fuel System Issues: Problems with the fuel pump, fuel filter, or fuel pressure regulator can cause limp mode.

4. Timing Issues: If the timing belt or chain is off, it can cause performance issues.

5. Knock Sensor Wiring: Sometimes, wiring issues, especially if there's been rodent damage, can cause intermittent problems.

It might be helpful to have a professional mechanic run a thorough diagnostic to pinpoint the exact cause.