I recently replaced my spark plugs on my 09 Saturn Aura XR 3.6L v6 using Bosch double iridium spark plugs. When I start my car, it has a rough idle and all of a sudden drop down to a very low RPM like around 500-1000 or so. Much lower than usual. I know that it's not an issue with the spark plugs themselves because this product does not need gapping as it's been preset to fit Saturn Auras. I made sure that the plugs are in the right ignition coils. I don't know what could be causing this. Any thoughts?

 

The plugs.

Use OEM PlugsAlways check the gap.


RockAuto

GM Parts Giant
Spark plug interchange tables are as you have noticed, are often useless.

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I agree with derf. I wouldn't put Bosch plugs in a lawnmower, let alone my car. They suck.