Cadillac Seville STS Rough Idle

Learn if it's a simple fix or time to seek out a trusted technician.

What are common reasons my Cadillac Seville STS has a rough idle?

While there are a variety of reasons your Cadillac Seville STS has a rough idle, the most common 3 are a vacuum leak, an issue with the spark plugs, or a problem with the ignition coil.
of the time it's
Vacuum Leak
of the time it's
Spark Plugs
of the time it's
Ignition Coil

Get your Cadillac issue diagnosed by a professional

Find a high quality auto repair shop or dealer near you

Related Cadillac Seville STS Questions

See what others are asking about their Cadillac Seville STS. Get answers from RepairPal's community of auto experts and enthusiasts.
Dealer said i need new spark plug wires but they were replaced about 15k miles ago
I have a 99 sts with a rough idle and hi pitch whistle under the hood. anyone have the same issue, i know its a manif...

Related Cadillac Seville STS Problems

Find the most common driver-reported problems that are to blame when a Cadillac Seville STS has a rough idle.
The egr control solenoid or egr valve may fail causing the check engine light to illuminate.
The egr valve may stick open, causing a rough idle and/or the check engine light to illuminate.

Cadillac Seville STS Rough Idle Repair Symptoms

A failing ignition coil can create several symptoms: Check engine light comes on Engine runs poorly or stall Increased emissions Reduced fuel economy Car won’t start I...Read More
When spark plugs fail, the engine will struggle. The check engine light will come on, and it may appear either solid or flashing. The driver would likely notice one or more of t...Read More