A few weeks ago, while driving up a steep hill at 50-55 mph during heavy rain, I experienced sudden engine hesitation and a drop in speed to around 35 mph. This symptom repeated on a second hill shortly after, and has also occurred on flat roads since then. The vehicle's OBD2 diagnostic scanner shows fault code P050
Thanks for the response, kev2! The car was scanned at AutoZone, and no other diagnostic codes were detected. I can only estimate that the idle speed seems normal — I don’t have access to a precise measurement tool. Could you please provide a diagram or photo showing the location of the throttle body and nearby components? This would be very helpful for accurate troubleshooting.
See attached image — the throttle body is located on the driver's side of the engine, near the top. Start with cleaning procedures: clean both the throttle body and its components. Avoid using K&N-style air filters as they can interfere with idle stability. Look for signs of vacuum leaks (e.g., hissing sounds or visible bubbles). Lime green markings indicate the IAC valve location; yellow markings show areas on the throttle body to clean. For a visual guide, check this video: https://www.youtube.com/watch?v=KpNx77rvC4Y
P0507 indicates an idle speed problem — specifically, the engine is running too slowly or idling excessively. A proper scan tool is recommended for accurate diagnostics. Check if any other diagnostic codes are present. What is your current idle speed? Look for vacuum leaks as a common cause. Clean the throttle body (TB) using a dedicated TB cleaner spray. Inspect and clean the IAC valve pintle located on the throttle body. Ensure all electrical connections to the TB are secure. Note: If this issue persists, there may be additional underlying codes — a reliable OBD2 scanner is essential; avoid using basic or low-quality code readers.