Posts Tagged: hunting idle
What is an idle air control valve and how does it work
Learn how an idle air control valve works An idle air control valve bypasses air around a closed throttle plate so the engine can get air at idle. Because it bypasses air, it’s also called an air bypass valve. Back in the days of carburetors, idle speed was adjusted by way of an idle speed screw that forced the throttle plates open by a crack. In fact, on many carburetors, there were two idle speed adjustment screws; one for hot idle and another for cold. Turning the screw inwards prevented … Read More
RPM fluctuation at idle — Most common causes
What to check if you have RPM fluctuation at idle If you’ve ever sat at a stoplight and noticed your car’s idle fluctuating—revving up and then dropping down repeatedly—you’re not alone. I’ve been there, and I know how frustrating and concerning it can be. A steady idle is one of those things you probably take for granted until it starts acting up. When it does, it can feel like your car is trying to communicate a problem. Fortunately, with a bit of investigation, you can usually pinpoint the cause and … Read More