Sorry if this information has been posted somewhere else, I have tried to search many different forums and threads to no avail. I actually found a few people that had the same problem but there was never a resolution posted. Anyway, I'm having a problem with my prelude misfiring at idle when its cold. The problem goes away when the car gets to normal operating temperature, and it runs flawlessly which leads me to believe there aren't any problems with the fuel system. I've driven the car over 100 miles while it was warm after resetting the codes and it didn't throw the codes again until the car sat overnight. The car is throwing the codes, P0300, P0301, P0302, P0303, P0304. So far I've replaced the spark plugs, checked the distributor and everything looks fine, I've cleaned the EGR port and the IACV. I should mention the miss usually continues through warm up. I really hate to keep throwing darts at this thing since I've already spent way too much money on it in the time that I've owned it. If anyone has any advice on this it would be greatly appreciated.

 

first thing what comes into my mind is that dizzy cap is gathering moisture (bad/old seal) and causes that....?

when you have changed distributor cap & rotor and spark wires?

 

Did you mention you replaced the spark plugs?
What about the spark plug wires? If the are very old they may be part of the faults.