Idle vibrations

[MikansT]

I got a 2006 Mustang V6 recently, it runs fine with no check engine light or codes. But at idle on park and drive, the interior and seats vibrate what feels too much. It does not do it when there's acceleration. Only on complete stop idles, it vibrates the seats, if I rest the back of my head on the seats it feels like a violent massager.
The Rpms stay steady below 1k

I'm not sure if Mustangs are meant to have vibrate or be smooth

Ive changed the spark plugs, plug wires, coils, motor mounts, cleaning the maf and throttle body, since I've read a lot of forums that that's helped. But they haven't worked on mine.
I'm just not sure what else to try or if the vibration is just a Mustang thing

 

[TGotschall]

Is it an automatic? I’ve seen loose converter bolts cause something similar. In another case, the converter itself. Worth looking into I would think.
Was going to suggest motor mounts but you changed those already.

 

[MikansT]

Is it an automatic? I’ve seen loose converter bolts cause something similar. In another case, the converter itself. Worth looking into I would think.
Was going to suggest motor mounts but you changed those already.

Yes it's a automatic, I'll try to have the converter looked at soon then, to see if that's what's causing it, thank you

 

[kdphoto]

Vibration gone — here's the fix on my 2006 Mustang Base.

I dealt with the same vibration at idle while in gear for about a year, and I finally tracked down the cause. The transmission fluid hadn't been changed in 119k miles, so I brought the car in for a fluid service. The mechanic explained that when the fluid gets old and thins out, the clutch plates in the transmission can chatter. After the fluid was replaced, about 80% of the vibration disappeared.

Ford calls it a "lifetime" transmission and says the fluid never needs changing — yeah, right. It should be serviced every 60k.

I also learned that a low idle can cause vibration when the car is in gear at a stop. I'm using an SCT tuner that lets me adjust the ECM settings, and I found I could raise the idle from 600 RPM up to 900. I set it to 800 RPM while in gear at a stop, and that completely eliminated the remaining vibration.

The car is running great now — smooth at idle and totally vibration‑free.

For the record, I had already replaced the spark plugs, wires, distributor cap, and even the harmonic balancer, and none of that made any difference. The fluid change and idle adjustment were the real fix.

 

[86GT351]

Vibration gone — here's the fix on my 2006 Mustang Base.

I dealt with the same vibration at idle while in gear for about a year, and I finally tracked down the cause. The transmission fluid hadn't been changed in 119k miles, so I brought the car in for a fluid service. The mechanic explained that when the fluid gets old and thins out, the clutch plates in the transmission can chatter. After the fluid was replaced, about 80% of the vibration disappeared.

Ford calls it a "lifetime" transmission and says the fluid never needs changing — yeah, right. It should be serviced every 60k.

I also learned that a low idle can cause vibration when the car is in gear at a stop. I'm using an SCT tuner that lets me adjust the ECM settings, and I found I could raise the idle from 600 RPM up to 900. I set it to 800 RPM while in gear at a stop, and that completely eliminated the remaining vibration.

The car is running great now — smooth at idle and totally vibration‑free.

For the record, I had already replaced the spark plugs, wires, distributor cap, and even the harmonic balancer, and none of that made any difference. The fluid change and idle adjustment were the real fix.

View attachment 113683

 

[86GT351]

Ford actually states 150000 miles. Industry suggestion is 60000 intervals.