1. Check your motorcycle's manual to find the recommended idle RPM. The ideal idle speed for your bike is listed in your manual. Flip through your specific manual to find the ideal RPM settings, which is usually around 700-1,000 RPM. Search for a copy of your specific bike's manual online if you don't have the hard copy. [1] Use a flat screwdriver to turn the idle speed screw to the right to increase the idle speed, or turn the screw to the left to decrease the idle speed. Start the engine and let it idle. If the idle is too low, turn the screw to the right a quarter turn at a time until the idle is at the desired speed. #1. My timing is correct and need to adjust the idle speed. It is low at about 615-620 rpm. How do I adjust it up? Is there an idle screw in the throttle body or is it not that easy..lol The FSM says that I do it through the IAC but dunno if this is it or if it is how do I adjust it at the IAC. thanks of any help. Step 1: Get ready to fine-tune your idle. After your Ford F150's engine has been running for a few minutes, shut it off. Turn the ignition key to the "off" position. Do not remove the key from the ignition switch. Step 2: Determine the location of the idle adjustment screws. With a wrench, disconnect your vehicle's negative battery cable. How to adjust idle speed in car engine. Years 2000 to 2015. How to adjust idle speed in car engine. Years 2000 to 2015. What RPM Should a Car Idle at? Wondering what the ideal idle speed is for your car engine? We've got you covered with this guide to help keep your engine running smoothly. By Magnus Sellén. Updated: January 7, 2023. Most people pay no attention to the car RPMs until there's something wrong. Open the hood of your vehicle and locate the idle control screw on the throttle body. Turn the idle control screw clockwise to make the engine idle faster or counterclockwise to make it idle slower. If you turn the screw too far in either direction, it may fall out. If this happens, turn it back one full turn and try again. DhHD6im.