Lexus IS Jerking Acceleration

Greetings. I own an IS as well, and your symptoms sound similar to a problem I encountered some time ago. Have you checked your intake manifold? Scorching can lead to leaks, causing issues like those you've described. Inspecting the manifold pressure might also prove insightful.

Thanks! When you mention scorching of the intake manifold leading to leaks, did you also experience similar symptoms such as reduced engine power and stalling? Furthermore, were there any specific error codes that were triggered in your case, and did the error point directly to the manifold?

Indeed, I experienced nearly identical symptoms. Reduced power, rough idling, and the check engine light were all present. While the error code itself wasn't explicitly 'intake manifold,' the diagnostics, coupled with a visual inspection, confirmed the manifold was leaking due to heat stress. Given your description, I'd strongly suggest having a qualified workshop examine the intake manifold. It's a common failure point, unfortunately.

Thanks for the confirmation and the advice. I will schedule an appointment with my trusted mechanic to have the intake manifold thoroughly inspected. It seems the diagnosis aligns with your experience. Your insights have been invaluable. The garage confirmed the intake manifold was defective due to scorching. The repair, including parts and labor, cost 1180€.