I took my 96 accord in yesterday, had engine light on, fuel bank miss fire but it was running ok. I had them change the fuel filter, now it is missing bad on cyl 3 & 4 they say. They say they check the distributor cap and cleaned it. Tried some new plugs. Checked the wires and all seems ok. Today they are going to check the fuel injectors. They suspect the ECU computer module? Seems kind of wierd it is all messed up from a filter change. Could more fuel coming really do all of this? Thanks for any ideas and or help? If I end up needing a new ECU anyone know where to get one? Are they expensive? Used one be a choice?

 

What are the original sp of 3&4 look like, are they brownish and dry, or black and oily? After replacing sp, 3&4 got oily real fast? If yes, I'd check compression for those 2.
Don't buy any fuel/ecu parts until they fully diagnose the misfire. What's the mileage on the car, and have you had dist cap, rotor and wires replaced before?

 

Thanks for the reply. I didn't think about all of that. A shop has it so I don't have the old plugs or know what the new ones look like. He says it is getting spark from the wires to the plug. Pulled cap off and cleaned it. Car has 206000 on it but it was running pretty good when I took it in before fuel filter replacement.

 

I'd pull all 4 plugs and inspect. If 3&4 are fouled I'd check compression. If compression is the same within 5-10% of all 4 I'd go after new dist cap and wires.
But before you can do the spray bottle test, at night in your garage - start engine and spray some mist on dist and wire area and check for arcing. That will give you some idea about dist cap/wire condition.