Is a rough idle at stoplights a sign of bad motor mounts?
Engine vibrations and rough idling at stoplights can indicate that your motor mounts are worn and allowing excessive movement. This makes it difficult to tell normal startup engine shift apart from failing mounts without checking for cabin vibration.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1cleaning the throttle body
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
r/AskMechanics1 person · September 2026
“Started having what feels like rougher idle at stoplights, signs, etc.”source ↗
robomed47 · r/AskMechanics · 3 upvotes
r/MechanicAdvice1 person · October 2026
“Is this normal engine movement for a start up? Are my mounts possible worn? Also feel slight vibration in cab when idle.”source ↗
ReporSS · r/MechanicAdvice · 1 upvotes
Where this came up
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