Rep Power: 0

Car - 04 Honda Civic EX Coupe
Mileage - around 66,000 at the time of the incident back in January.

Back in January my check engine light came on and then when I pulled over, it went off. Then a week later when I left my job and drove less than a half a mile to get food and while driving, it felt like the engine was jumping (what I'm assuming was the cylinders were misfiring). Starting to drive home when it did it again and I got a check engine light so I went to the Autozone that was again less than half a mile from where I was. I got there right as they were getting ready to close so they weren't being much help but I did get these codes:

-OEM Number to Cross:P0301 (Cylinder number 1 misfire detected)
-OEM Number to Cross:P0302 (Cylinder number 2 misfire detected)
-OEM Number to Cross:P0303 (Cylinder number 3 misfire detected)
-OEM Number to Cross:P0304 (Cylinder number 4 misfire detected)
and maybe
-OEM Number to Cross:P0300 (Random/multiple cylinder misfire detected)

but not sure about the last one cause they didn't print them all 8 out but I know all 8 codes they got were all pertaining to the cylinders misfiring.

Their list of probable cause:
1. Vacuum leak affecting one cylinder
2. Ignition system concern
3. Blocked/faulty fuel injector
4. Engine mechanical condition

The guy who was helping me did say that it was odd that they all would misfire at the same time and that he thought it was something that connects them all together was going bad (I don't remember what he called it). So I drove home and it didn't happen again. A week later, the check engine light went off. A family friend who works on cars said to keep driving on it till it does it again. So now I've been driving it for a month and the only thing that doesn't seem right is that the car shakes when I'm between the speeds around 50 mph to around 65 mph (which it started doing after the first time the check engine light came on).

I'm also wondering if its was just a one time occurrence and the shaking is cause by something else. I'm also wondering if its safe to drive for a long distance (600 mile round trip) in late March or if I should try to get it checked out before then because I don't want to break down that far away from home like I did last year when one of my cylinders blew because I apparently didn't have any antifreeze in the car and it overheated. Yes, I did check to make sure there was antifreeze when it did this.

Side note: I also just got out of college and currently working two jobs so any suggestions on what is wrong, how to fix this problem myself, or anything like that would be great cause I don't really have the money to just throw at possible solutions that would only effect one cylinder.

 
Rep Power: 312

Hmmmmmmmmmm....................................... ..... This could be so many things its ridiculous... Check your timing belt A.S.A.P though. Sorry I can't be of more help, it's just too general to even attempt to diagnose online.

 
Rep Power: 0

I ended up doing a tune up and didn't have a problem for another year (when it got cold again) and then it was suggested that there might be a build up of water in my gas tank and to just use some gas treatment. I will see if it acts up again this winter (if it ever truly gets here). Any suggestions on what type of gas treatment to use?

 
Rep Power: 0

I have the same problem but it doesn't go away any luck on it yet?

 
Rep Power: 511

it really could be a number of things.. Got any more specific information on your situation? Recent maintenance done, location might be pertinent (salt on roads can cause/exacerbate corrosion), etc?

 
Rep Power: 0

We had the same issue. Just bought the car and the coolant dumped into the oil. Blown Head Gasket.