Questions and Answers

Jeep Grand Cherokee Hiccups Q. I bought a 2001 Grand Cherokee Limited two weeks ago. 44,000 miles, 4.7 liter V-8. Any time I turn the heating or air conditioning on I feel mild repeated hesitations or hiccups. I can feel it about five times a minute at any speed. When turned off, no problem. Took it to dealer and there was no fault code. All computers were reset but problem still there.

A/C and heating both work fine. Recent tune up and service. Any idea?

Best Regards...

A. This is going to be a tough one to find. But since it only happens when the A/C is on, I would have to suspect the Idle Speed Control (IAC) actuator or Powertrain Control Module (PCM). It could also be a bad A/C Low Pressure Sensor.

The first thing to do would be to carefully inspect the connectors and actually terminals to be sure they are clean and tight. I would also recheck the refrigerant charge to be sure it is full. Low refrigerant is the primary cause of the surging you describe.