u/HuhIDontWorkHere

97 mustang GT 4.6l sohc automatic.

When im coasting this noise starts. If I give it gas and accelerate it will go away. Only happens sometimes during coasting at low rpm.

Update: after market idle air control valve is causing this. Resonance issue which can be solved by using a smaller hose or you can put a zip tie around the idle air control hose, and just pinch it slightly. See attached link

https://stangnet-com.cdn.ampproject.org/v/s/stangnet.com/mustang-forums/threads/resonate-noise-from-iac-valve.866051/?amp=1&amp_gsa=1&amp_js_v=a9&usqp=mq331AQIUAKwASCAAgM%3D#amp_tf=From%20%251%24s&aoh=17791488961385&referrer=https%3A%2F%2Fwww.google.com&ampshare=https%3A%2F%2Fstangnet.com%2Fmustang-forums%2Fthreads%2Fresonate-noise-from-iac-valve.866051%2F

Update Again: cable ties helped, but seem to loosen with multiple drives because of engine bay heat. Removed those and I am attempting a hose clamp instead, if I dont report back it works.