Honda misfire codes 2001 civic, three of 4 cylinders and random misfire any idea?

Car actually runs fairly good but I see the misfire come on while driving
I checked compression, seems fine all cylinders
new plugs, new air filter, cleaned throttle assembly
checked by pulling spark plugs one time no dead cylinder
gross check on injectors didn't see anything
two cans of injector cleaner
1 can seafoam in gas tank
changed oil
any good suggestions?

Thanks Long
2001 Honda 148K miles,
185psi dry were all pretty consistent compression (warm not hot, not cold)
all spark plugs were removed when checking, did not try wet readings
unplugged fuel injectors one at time, no real difference
don't know vacuum, will have to figure that out
don't know exh backpress will have to figure that out

I rechecked codes today and only P0302 (cylinder 2) now
Vacuum leak? Ignition? Fuel Inj? Other?
I paid attention this morning and basically from cold start to 5 minutes driving ETL it starts to flash (misfire?) when running ~3000 rpm and then at stop light idles and misfires stop.
I'm going to listen to FI tapping tonight on 2 vs other cylinders.
I'm going to spray/bubble test vacuum tonight to look for leak.
ANy other idea? Swap a new coil for 2 or waste of time?

So like you have mentioned in your E mail: P0300, P0303 and P0304. I need to ask you a few question and need more information on the Civic:

Btw: Is the CEL on then off, flashing or solid lit up?

1- Give me the exact compression readings. I assumed they would be a "dry" readings. Do the "wet" compression test and the cylinder leak down test would be helpful.

2- What are the vacuum readings? Both would be at idle and at 1500 rpm.

3- A fuel readings would be wonderful (With and without the fuel pressure regulator hose connect/ plug hose)

4- Have you check the EGR system? MAP? Intake gasket for leaking?

5- Explain to me how did you check the injectors? Electrical/ Mechanical ways?

6- How many miles on the car?

7- What are the exhaust back pressures?

8- Swapping #3, #4 injectors to #1 and #2 and see if the codes are follow if you have no way to check for the spray pattern.

You have my E mail address. I'll reply the fix as soon as I have the answers from you. Happy wrenching.

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