[Dylan Bannon]

So I was driving down the highway and my engine started misfiring really badly. I scanned the codes, and it gave back P0300-P0303. According to the guy at Autozone, it's probably bad ignition coils. Is there a way to test the coils to see which ones are bad or if they are? I'd rather not replace them all if I don't have to. I have a ScanGuage II and a multimeter, and I could probably borrow some other tools if they would help me diagnose the issue. Thanks for the help.
-Dylan

 

[Coltello]

So I was driving down the highway and my engine started misfiring really badly. I scanned the codes, and it gave back P0300-P0303. According to the guy at Autozone, it's probably bad ignition coils. Is there a way to test the coils to see which ones are bad or if they are? I'd rather not replace them all if I don't have to. I have a ScanGuage II and a multimeter, and I could probably borrow some other tools if they would help me diagnose the issue. Thanks for the help.
-Dylan

When's the last time you did the plugs and coils? It might be time to replace all of them even if only one or two are currently malfunctioning. But VCDS scanning should tell you what cylinders are misfiring.

 

[Dylan Bannon]

It's been a couple years since I did the plugs, but I replaced two of the coils last year, although the ones I replaced them with were used. How long should they last? What about sparks?

 

[Coltello]

Rather than type:

http://www.ngksparkplugs.com/techinfo/spark_plugs/faq/faqchange.asp

I plan on swapping out my plugs every two years. It sounds like it's time for you to do plugs and coils now though.