It's a 93 sc300 with the ge engine. Let's start I bought the car dude said fuel ecu was out and had a new one in the back seat I just had to plug it in. The car idles fine and in park and can Rev it up no problem but when you go to drive it and go to push down the gas even if you push it to the floor the car takes forever to accelerate. Like its pulling a boat behind it. So did the cap and rotor, plugs and wires and put in the new fuel ecu in the car but the same thing. I've tried looking everywhere on forums but can't find anything. Oh and did a compression test and everything was okay

 

Might be in the ECU itself. Several older Lexus products had a problem with delayed throttle and transmission response in their throttle-by-wire systems. Modern vehicles don't have a direct mechanical connection between the gas pedal and the fuel-injectors.....it goes to a computer, which analyzes the signal and sends a response to the spark-timing and fuel injectors as needed. Some of the Lexus ECUs had problems responding to demands for acceleration from low speeds...especially from, say, a 5-MPH rolling-start. Factory re-flashes for the ECU's software/programming were supposed to take care of that problem (and that of RPM-flaring during transmission shifts)...but often had little or no effect. I had a 2001 IS300, and went through some of that myself.

 

Checked fuel pressure?

 

Carbon build up.

 

plugged CAT Converter??