Not always, but sometimes at a red light, the idle RPM needle tends to move up and down a bit. Could this be due to a dirty throttle body or a catalytic converter issue?
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Its normal dont worry about it. My 2014 scion frs has been doing this since i bought it at 28,000 miles. Its at 97,000 miles now. My frs makes so many weird noises i just dont notice it anymore lol
Yes, fluctuating idle RPMs at a red light can often be attributed to a few common issues, including a dirty throttle body or problems with the catalytic converter. A dirty throttle body can cause irregular airflow, leading to unstable idling. Similarly, issues with the catalytic converter, such as clogging or overheating, can impact engine performance and cause idle fluctuations. Other potential causes could include vacuum leaks, issues with the idle air control valve, or problems with the fuel system. It’s a good idea to have a mechanic diagnose the issue to pinpoint the exact cause and get it addressed properly.
You’re not alone! Idle RPM fluctuations can be annoying and a bit concerning. Here’s what I found based on my research:
- A dirty throttle body (engine’s air intake) is a common culprit. If it’s clogged, air flow gets wonky and RPMs bounce.
- Catalytic converter issues are less likely for just RPM problems, but possible.
- Get your throttle body cleaned by a mechanic - it might fix it!
- See a mechanic for a proper diagnosis. Better safe than sorry!