Misfiring Code 300

[moneyshotz]

Hey
I just got an SES light and when I took it to autozone they said I was having some random misfires. Any reason why my car would be doing this? I have like 53k did my plugs and wires go bad already?

And I was just wondering if this related to the reason why at 3rd gear after my car locks-up and I just tap the gas(like 1/4 throttle) I hear this bad "grinding" noise. If so, what brand should I go with?

[mcG]

i was just at autozone today and had a similar problem, except it was just cylinder 5 that was misfiring...the guy recommended getting a full tune up, that should solve the problem

[black98V6]

man if you are getting random misfires you might have bigger problems that just a plug wire thing.. that usually results in a particular cylinder or 2 misfiring..

[moneyshotz]

So what do you recommend that I do? Anything else that can be wrong?

[black98V6]

first thing I'd do is clear the codes.. drive around let it set the code and see if you get the same one again.. if you are still getting random misfires and not just a cylinder or 2.. well the "easy" route would be to change the plugs and wires and see.. beyond that you really have to get to diagnosing.. could be crank position sensor, pcm problem, coils.. coil interfaces... see what I am getting at.. at that point I'd be taking it to a professional.. a quick thing would be to get under the hood and make sure everything is tight.. a good way to do this is to say comptelety disconnect a plug and reconnect.. not just grab it and wiggle.. auctually unplug and re-plug it..

[Ted]

Before going off and doing all this. This is what I would do. Take off your spark plug wires one by one. Get an ohm meter (if you don't have one borrow one from a friend or you can get one for like $15) check the resistance on each wire by putting each lead into the different ends. If the resistance is over 30,000ohms the wire should be replaced, but it should also be under 25,000 ohms for a good wire. Next pull the spark plugs and check for severe detonation. Replace sparkplugs if needed. Reset the pcm and drive around to see if it throws a code again. If it does then I would move on. Locate your coil packs. Take each one of them off and test for the resistance. Check the resistance between the primary terminals, it should be from .50-.90 ohms, then check the resistance between the secondary terminals it should be from 5,000-10,000ohms. If any failed the test then replace the coil. If any of these didn't fix the problem then I would look into spending the extra money to getting it further looked at. But these procedures are things that everybody should know and beable to check them selves before taking it to a shop.

Hope I could help