hi,

need some help here, I'm driving a 94 model Accord with a H22A engine and manual gearbox. The problem I'm having is whenever I start the car when the engine is still cold (overnight or after long stop), it will idle as if it's running with 3 pistons only, quite rough and the engine is vibrating.

After driving for over 20 minutes, then this problem doesnot occur anymore, smooth idling.

I've checked the vacuum hoses, service the injectors, replaced the distributor, spark plugs and plug cable but the problem does not go away.

Is there any other thing that can cause this?