Cobra troubles

[02SonicGT]

I have an 04 with 78k mikes. Only mods are a JLT rai and Borla catback. When I let the car idle or drive it has developed a slight miss. When it misses every light will pulse as well in sync with the motor miss. I did recently purchased a new battery. The shop I had it to couldn’t figure it out and said there was nothing wrong with it. And idea on where I should begin?

 

[rymax101]

Sounds like a sprak plug or coil pack short to ground

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[olympic]

Remove the spark plugs and coils and look for oil in the bottom of the plug wells. If there is, you need new cam cover gaskets, plug well seals, spark plugs and coil-on-plug boots. If the wells are dry then you can closely inspect all of the coils and spark plugs for signs of arcing.

 

[02SonicGT]

I forgot to mention. Last time the car was missing the lights never pulsed and they replaced. Cooilpack and it ran great.