One problem related to emission control has been reported for the 2007 Chevrolet HHR. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2007 Chevrolet HHR based on all problems reported for the 2007 HHR.
I own a 2007 Hhr (mileage 10753). It is easy to drive, is roomy and economical to operate. I had a very scary experience last evening while driving the Hhr on an expressway in traffic. The motor shut off completely. The lights, radio, etc continued to work properly. The warning message was "engine power reduced". I made it to the side of the road. The car would not restart. No sounds, clicks, nothing. I waited a few minutes and the car started with an engine warning light on. I got off the highway and had something to eat. I went out and the car started up without an engine warning light. I took it to, holler Chevrolet (winter park, FL), this morning. Holler Chevrolet replaced a chip (pcm) and said it would be fine. Mike laing at holler represented both gm and holler with professionalism, skill and dignity.