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Ok, so it all began very suddenly, it did slowly progress and get worse (and still is, and by worse, i mean more frequent). Initially it just began misfiring when under a lot of load. Once the Check engine light finally came on, I had it read, and it came up with P0300 P0301 and P0303, which are Random Misfire, Cylinder #1 Misfire, and Cylinder #3 Misfire. So i checked the plugs, fine (brand new E3's), checked the coil packs looked good but I switched the #3 and #2 packs just to see. Reset the Light, Looked in the engine bay for bad wires didnt see anything. Drove for a while it progressively got worse, it would start to do it sometimes at idle, but never during light (very light acceleration), and other times it would never do it. Once the light came back on I had it read and it was the same three codes from last time. So its not the coil packs. I've changed gas 3 times. I dont think its the injectors, or head gasket. It's not running hot or losing coolant. I would think it'd be hard for 2 injectors to go bad at the same time and still, what about the random misfire code? It has gotten to the point now that it does it more often than not, but there's still a few times where I can accelerate and put as much load as I want on it and there will be no misfiring. I'm really at a loss as to what's wrong. I had 2 very good mechanics drive it and look at it and both were stunned at the inconsistency of it. The hardest part to figure out is why it doesn't always do it. This has only been over the course of 2 and a half days, but yesterday I barely made it home and the same today. I really need some help so thanks in advance! please ask any questions I haven't covered in this really long explanation.

 
Rep Power: 811

first thing you do, change back to NGK or denso plugs. even a regular $2 ngk copper plug will work. the E3 are complete garbage. i dont think its a headgasket leak, because even if coolant is leaking in the engine, it will burn off and not misfire anymore while driving. the coil pakcs could be an issue, take them all out and measure the resistance values using an ohm meter. they should all have nearly the same resistance. if one is different, its bad. also check your ground wires in the engine bay, be sure they are not corroded or loose. otherwise only other things that cause misfires while driving are plugs, clogged injectors, low fuel pressure (from bad pump or clogged injectors), or something wrong with the air intake system like a big chunk of stuff caught inside, maybe even leaves. oh yeah it could also be a clogged catalytic converter. start with the cheap stuff and work your way up.

 
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I'm sooooo happy! I went and got the $2 NGK V Power, and swapped em in just to see... turns out E3 are total pieces of ****! I'm going to take them back and ask for a refund! I can not believe i went through all this to find out that it was expensive spark plugs gone bad in 6000 miles! Thank you so much dude! I am amazed it was those E3's, they really worked well when they were in there though, it felt like an additional 15 hp. I wonder why they went so bad so quickly. Anyways thanks again.

 
Rep Power: 811

haha yup whenever i see ppl post about misfires and say they have e3/bosch/autolite etc junk plugs, i always know its gotta be that.

the vpower are good plugs, will prolly last around 20-30k miles, but prolly better to change em earlier. or if you really want the best, go with denso iridiums which are around $32 for a set of 4 on ebay. those use the least energy and have the best performance. their life is only 3 yrs/30k miles tho similar to copper, because the electrode is small. mine are 2 yrs old and still feel like new.

 
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I'm thinking about picking up a set of the NGK iridiums when I go demand a refund for the E3's. haha. I still am shocked after all the good things i've heard about the E3's and Bosch that they're so terrible. It's kinda sad cause they were nice plugs, for the little while they lasted.

 
Rep Power: 811

yeah ngk iridiums are also good.