Rep Power: 0

1996 Civic, Automatic

In the last 2 days, the engine has started missing at idle when fully warmed up after driving for more than about 20 minutes. It is not surging, it is missing. When not missing, it idles perfectly. If you let the car cool down for about 30 minutes and start it, it runs perfectly until heated up again.

Check engine light has NOT come on.

Code reader shows no stored codes.

I took off the air cleaner, and the throttle valve and intake looks perfectly clean.

I cannot find any vacuum leaks.

Distributor cap does not show any cracks - I've looked carefully.

Since it runs fine until fully heated up, my thought is that it isn't spark plugs or wires from distributor

Car has under 60,000 very easy miles.

I would appreciate suggestions on where to start looking. Thanks.

 
Rep Power: 0

Since it showed no stored codes, I took photos of the live data when idling just in case it is helpful:

 
Rep Power: 0

I have a similar problem on my 2000 EX D16Y8. I'll let you know what I find.

In a past car, I had an '06 Ford Escape that had a rusted actuator on the IAC valve. I'll be looking at that myself on the Civic.