Rough idle, Code P0301, traction control light, hard shift to first gear

YANNICRISANTOS

MEMBER
2010 CHEVROLET HHR
2.2L
4 CYL
2WD
AUTOMATIC
139,000 MILES

After switching back and forth on the spark plug, ignition coil, to try to find issues with the engine misfire I did a compression test. Cylinder one 148, cylinder two 185, cylinder three 183, cylinder four 180. Any information on what to do next to fix this issues would be helpful!

1 Reply

HMAC300

MECHANIC
48,601 POSTS

Compression is not too bad. 301 is a misfire code which are very hard to detect the problem even for pros. it is best to have them do it as they can do stuff with their scanner that you or auto parts cannot. you can check for a vacuum leak and fuel pressure and maybe spark to all cylinders if accessible, but other than that let a pro fix it. See link.
https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator