Lexus GS430 engine decelerates when accelerator pedal is depressed, worsening in gear on Lexus GS430

Some Lexus GS430 owners report experiencing engine deceleration when the accelerator pedal is depressed, particularly worsening while in gear. This issue may manifest as engine hesitation, where the vehicle ignores the initial 20% of accelerator input, leading to a jerky response. Additionally, owners have noted loss of power and noticeable hesitation while driving, which can signal serious engine problems. Gradually increasing symptoms such as power loss, sluggish acceleration, and decreased fuel economy may be attributed to dirty fuel injectors, engine valves, and combustion chamber deposits. To address these concerns, it is recommended that owners inspect and clean fuel injectors, engine valves, and combustion chambers, as well as check the MAF sensor, air filter, and engine oil for dirt that could impact performance. Furthermore, checking the O2 sensor for faults is advisable, as it may send incorrect signals to the engine, resulting in inefficient fuel usage.