2005 Explorer 4.0l 111k mi. Just changed plugs & wires. Still hesitates/chugs but only at RPMs under 1800 and only when accelerating slightly. No problem at startup or higher RPMs or with moderate acceleration.

Any suggestions?
Thanks.

You might have a bad coil pack, throttle position sensor, or MAF sensor. Any chance you have access to a scan tool with the datastream mode? Have you tried gas from a different station?

-Rod

No, but I know a repair shop that does. I had hoped the "only a low RPM symptom" might isolate the culprit, but maybe not.
Any other suggestions?