I finally decided to pull the denso iridium plugs out of my wife's accord after about 5 months of using it. It was giving me really bad gas mileage, really bad idle and worse throttle response. At one point, I almost thought it was because the engine is getting old (60k miles). I finally took the plugs out last week and replaced it with NGK V-power copper plugs. The bad idle is gone, the bad throttle response is gone. It even shifts smoother now (auto tranny), no more jerking at low speed shifting.

I still need to check the gas mileage later on and make sure the plugs is what cause the low gas mileage problem.

If anyone has similar experience with iridium plugs, I would recommand swapping them out right away.

 

there are different temperature range with iridium plugs. Did u get the he right one? Some plgs are for turbo car others are not.

 

Just like the little toyota story, the little shoelace size sparkplug wires on their new toyota works best, anything aftermarket=big headache

 

the plug is what's listed for a stock accord in the Denso catalog, so I believe it is the right one.