I have a 2000 Accord sedan with a V6. It has 92k miles and an automatic transmission. Sometimes when I start the car after it has been driven for a bit, it idles rough for a few seconds and then returns to normal idle. It doesn't have any trouble maintaining a smooth idle after running for a few seconds. It doesn't do this every time, just randomly.

Any suggestions?

Thank you all for your help in advance.

Jason

 

Have you ever cleaned the fuel injecton system?If not that could be it

 

Try this first; turn the key on, then put on your seat belt, then crank the engine.
The idea is to allow the fuel pressure to reach it's peak so the injectors spray out a fine easy to ignite mist, as opposed to a low pressure dribble.
If you feel it is a flooding problem you can open the throttle 1/2 wayto allow more air when cranking under those 'special' conditions, and if you floor the gas pedal it will turn off the injectors when cranking, this method is used to clear a 'flooded' condition.
If this info. doesn't help, you might consider an injector leak down test.
The owners manual has some info about this and shorttrips/ rough startsare a known problem.

 

Thank you for your assistance and suggestions. I will give the key on, seatbelt, and then crank a try and see what happens.

When the starting condition occurs, it feels more like the car is starved for gas than flooded. The engine idle drops very low and then weakly comes back up to around 900 rpm, then drops again. Eventually after 2 or 3 cycles of this up and down, it levels out around a smooth 900 rpm. Once it passes, it drives fine.

The throttle body was cleaned recently before I bought it, as it apparently was running rough with a check engine light on at that time. Since it was cleaned, the light hasn't come back on. I put a bottle of fuel injector cleaner in a 1/2 tank on Saturday and will see what that does, if anything. I had the PCV valve replaced today also.

Any other suggestions are appreciated.

Thanks again.
Jason