Hi everyone,

I've had this problem with my Civic for a while now and have not been able to figure out what is wrong. Occasionally, when I come to a stop, the RPMs will drop a bit lower than it seems they should (the needle is almost on 0) and the the car shakes for a moment, then smooths out a bit. Also, it generally only occurs when the car is hot. If I drive it somewhere, park, and then return home, it happens on the return trip. It also happens more often in summer, but I don't think it is linked to the AC becuase it happens even when the AC is off. The car is stock, I have not made any modifications.

I have tried a couple of obvious things like changing spark plugs, air filter, and I had read that it may be an EGR valve problem so I did the "pinch" test and it made the clicking sound, so I assume it is ok?

Also, I don't know if this might be related, but at my recent SMOG check, the NO2 (I think it was NO2, I dont have the paperwork anymore) measure was high. It still passed, but it seemed unusually high (above the listed average, and most other measures were nearly 0). Any chance whatever might cause this could be relating to the other problem?

I'm hoping this is enough info to make the answer just pop out to someone.. lol. I don't really know much about cars, so, please help me!

Thanks.