My 2000 Accord V-6 intermittently feels like it is running on about 3 cylinders when I start it. If I rev it up, it smooths out a little, but still has a definite miss. Won't idle without holding the throttle open. Sometimes after shutting down and re-trying a half dozen it will finally start and run normally. This only happens occasionally, used to be once every couple months. Now it is every couple days and getting worse. Has not happened when starting cold (yet). Is this a symptom of a failing main relay?

 

it could be a lot of things.....do u notice any smells like fuel or excess exaust? you could have a valve sticking too...hmmm...

 

Is your check engine light turning on? Stop by a parts store and have them scan for code(s). They do this for free. Get the actual code and post it on here, it will start with the letter P and have four numbers, like P1234.

How many miles are on the current spark plugs? What brand did you use?

 

No CEL. Plugs are platinum, don't remember the brand. Replaced them about 10,000 miles ago. Made a non stop 170 mile trip yesterday, no problem. Parked car in driveway. Went out to put it in garage, ran like crap. Started this morning, ran perfectly. Car has 110,000 miles.

 

If the plugs aren't the brand and heat-range specified by Honda, then I'd yank those plugs, throw them in the trash (especially if they're Bosch), and then buy OEM plugs (I'm guessing NGK PZFR5F-11 or Denso PKJ16CR-L11, your Owner's Manual will have the correct spec).