{PLEASE HELP!} Multiple Random Misfires

[Slow y Low]

Here's the run down...car is misfiring on ALL 4 cylinders. Went to get the codes looked up, 5 in total came up. P0301, P0302, P0303, P0304 and also P1399.

P0301-0304
Definition: Cylinder 1-4 misfire(s) detected
Probable cause:
1.) Vacuum leak affecting one cylinder
2.) Ignition Sytem Concern
3.) Blocked/faulty fuel injector
4.) Engine mechanical condition

P1399
Definition: Random cylinder misfire detected
Probable cause:
1.) Blocked EGR passage
2.) Valve clearance out of range

So I noticed my Ek started acting up a few days ago. It was sputtering just a little when I was at a stop. Didn't think anything of it. Cut to yesterday, I had been driving through traffic to get to my buddies house. Hung out for a while then left, going out of the driveway the car stalled. I primed the fuel pump, started it up and it idled alright, slight misfiring . Driving it was a different story. A lot of hesitation and lots of backfiring, I was barely able to make it home.

Today I cleaned the throttle body and IM with spray cleaner, removed the ignition wire set and cleaned them (NGK Blues are about 4 years old), changed the spark plugs (needed to be changed anyways), and adjusted the valve lash clearance (I could hear some light tapping, plus it needed it) but nothing helped. Still runs the same. So now I'm too damn tired to work on it anymore so I'll go at it tomorrow. I'm going to change the fuel vacuum lines tomorrow since they are really old and its a cheap fix. I'm also going to take the EGR off and clean it up. I heard the IM can loosen up so I'm going to torque it down tomorrow to see if that helps. Also, the fuel filter is about 1yr old...I think. Should I consider changing it? I hate to admit it but I ran the tank to empty a few times this past month, so I'm thinking the pump could be going out but I've heard that they either work or they don't...FACK!!! SO MANY VARIABLES!!

Have any of you guys ever experienced these issues with your 6th gen civic? Feel free to share/help if you can!!

 

[civicexkid]

check you dizzy and all that look at the cap etc if you changed you spark plugs and wires are still fine look towars th distributor as its most likely something to do with that. thats te best i can give you i come from a k-series which have coils and a little easier to work with i think.

 

[Slow y Low]

I changed the distributor cap and rotor in Dec. of last year. I'll check it out just in case, maybe I'll just get a new set since I have the lifetime warranty from AutoZone. Thanks for the input yo!! Wish I had k20 power...

 

[Slow y Low]

O.k. so my motor doesnt have an EGR but it does have an IAC valve, which I removed and cleaned very thoroughly. While I was at it I cleaned out the Fuel Injector Air Control Valve as well. Finally I replaced most of the fuel vacuum lines and others that were old....the car runs a little better but is STILL misfiring!!! No CEL has popped up...yet.

Only other problem I can think of is the wires are shot but is it probable that ALL four went bad at the same time??? I'm also thinking the fuel pump is going bad?? It did die on me a few times when i was at the stop sign...I don't want to spend a sh!t load of money taking it in. I feel like I'm getting closer!

 

[Slow y Low]

I'm replacing the fuel pressure regulator today....going to see if that helps.

 

[chromal]

My D16Y7 started to post misfire codes when the fuel filter clogged (still on factory fuel filter at 215K at the time), but only while accelerating @ WOT and above 4-5K RPM (it felt like a fuel cut). But it seems like you're on the right track to suspect the fuel delivery and ignition systems.

 

[Slow y Low]

I see. My car has the same issue while accelerating. I'm going to go ahead and change out the fuel filter just in case. Thanks for the advice!! I think I'm almost there...