got two codes when check engine light came on
 

so i went to Autozone today and had them run the test, two codes came back


P0301 Code - Cylinder #1 Misfire
and the other one (cant remember the code) but it was basically the fuel filler cap not on or tightened.

i dont think its the first code since im not hearing or feeling anything different from the engine. it could be the fuel cap not being on all the way, but its on there nice and tight

I assume you tightened your gas cap to solve the 2nd.

So what is the question?

When was the last time you changed your ignition coils, spark plugs, and plug wires?

OP, please provide information... we are not mind readers.

Year, Model, Miles, Maintenance, current issues.

Thank you for providing the trouble codes.

Either code by itself will illuminate the CEL

The evaporative small leak is typically the gas cap. On the older RX8 models there was a defective vent and the cap must be replaced.

The misfire code is warning of a weak coil. Ignoring it can lead to wasted gas filling and killing your Cat convertor.
Typically the code means it is time to replace the coils but could also mean that your plugs or plug wires are no longer up to spec due to poor maintenance.

sorry should of put in the other stuff, 2004 RX-8, a little over 87,000 miles.....when i got the car report all recalls (mandatory and optional) were done, I'm only the 2nd owner. oil change about 3 months ago and always make sure the oil is at a good level.

i tried the 2nd option and the gas cap is tight, it might be that i have to replace it.

any other test i can do to see if it might be the coil??

Misfires can also be a number of other things other than ignition failure, including e-shaft sensor fouled, MAF dirty, vacuum leak, cat failure, compression failure, missing intake screens, and intake manifold valve problems.

It is usually ignition however.

If you don't know when the ignition was last changed, then replace all 12 pieces (4 coils, 4 wires, 4 plugs). Can buy all of these parts for as cheap as ~$192 and replace them yourself with basic tools and an hour's work. A dealer will charge you nearly double that just for parts, and then another few hundred for labor.

If you want to test the coils, do a search on here for DIY Coil test.

i think it showed the date of 2006, if not then looks like its time to change the ignition

Hopefully they were changed more recently than that. The plugs should be changed every ~20k miles the coils are hard to say some have them last for a while others say every ~30k miles give or take. You can get a stock set of wires for pretty cheap from rockauto and maybe even the coils as well. Autozone has the plugs(need to be ordered) for $20 each.

yea i dunno how often he or she did it, but will get them to order the full set and hopefully get this done this weekend