Hi all and thanks for any replys in advance.
So here goes, i have a 05 honda civic 1.6 vtec. I have read so many posts here and elsewhere but am totally miffed at cause. My civic has been on dignostics and shown p0301, p0302, p0303 and p0300 codes. So have random missfire. Have changed all the useual susspects, ign coil leads, spark plugs, oil and filter with treatment (still on max level), fresh tank of fuel with injector cleaner and also valve treatment. But all still the same after pulling ecu fuse and battery. light went of for a bit but missfiring still occuring and light now back on. Went to local honda yesterday and the tech there say's check vtec valve for being sludged up and do a compression test? A friend of mine is mechanicly minded and says crank/cam sensor? but surely a different code would appear? Am i right in thinking that vtec valve (solenoid) would have an individual code and also diag machine say if needed to check compression? As i say in beginning of this essay i am totally unaware of what to do next and any advice would be greatfully accepted.

 

may i also please add that its mainly under load.

 

how is your coolant level by chance? its not low or runs rough on cold startups? you said valve treatment, not sure what that is but have you had the valves adjusted?

 

hi and thanks. Coolant level is at max. If anything i runs a little better on cold start?