rich Z

For many months now when I stop at a signal the idle will be slightly low, 100-200 rpms down and then the the motor wil rev up to normal idle around 800. On sat I changed the spark plugs and wires and about every 30 secs the idle would go down to 400-500 rpm like it was going to die then it would rev back up to normal idle. I checked the plug wires for tightness and there fine. I have a vacuum gauge pod inside the car and normal idle it will show 22 hg and low idle 24 hg. I already took the IAC off and cleaned it with intake cleaner. It was full of carbon. Doing that didn't help though. The car runs good other than that. It's not missing or anything like that would indicate a ignition issue. I have used a piece of vacuum how to listen for vacuum leaks and notta they would show on my gauge anyhow.

rich Z

Today a couple times when rolling up to a stoplight in neutral the rpm's will go down to 500-600 then when I go into gear the rpm's come back up.