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2003 Honda Civic P0300, P0301, P0302, P0303, P0304

I posted a recent question on “Bad Gas” and I got several suggestions. I have a 2003 Honda Civic w/ 102K miles. Just a couple days ago the check engine light came on displaying these codes (random misfires in all four cyliders). My car began shaking real bad upon acceleration in any gear. It feels as though the car struggles to figure out how much to accelerate at any point with a steady foot on the pedal. I just filled up my gas tank the about 5 miles prior to this (about 9 gallons of fuel), and I thought it may have been bad gas but I am unsure as it is rare. I received several different responses, but I was looking for a more focused route to take when I bring it into my mechanic tomorrow. I have read several discussions suggesting I may need to replace the plugs, wires, dist cap, or coils. Are there any other things I should look for to possibly help out? Thanks for all of your help and support!

With so many variables to what makes an engine even run, much less, run well, do you think it reasonable to ask for exactitude? Sure, it would be nice to discover a silver bullet; but, such a thing isn’t what we have available.
The suggestions you have received start cheap, and easy. The next steps could be more difficult—even, requiring some testing and other diagnostics.

Hellokit makes a good point.

Personally, I suspect the latter will be necessary in this case to properly diagnose.

You MAY have an ignition system or computer fault here.

What I mean by that is, there may be an interruption in the electrical flow to the injectors.

I find it somewhat difficult to believe all four coils are acting on their own to cause your problem.

Based on the info provided in your previous post, ok4450 provided the focused approach you are seeking. Discuss his comment with your mechanic. Discuss symptoms with your mechanic, and have some knowledge of past maintenance (like 90K service, etc) that may bave been done by others that your mechanic would not have knowledge of. Beyond that, I think we all concluded diagnosis and on the scene inspection of the car is needed. OK4450’s comment:

“Normally one would suspect the crank sensor on a multiple misfire problem but the ign. switch could also cause this. Since the switch is fairly simple and free this should be done first rather than spend any money or use a shotgun approach to any repairs.
Here you go.