2006 Chevy Cobalt Chevy Cobalt missing on 2 cylinders

ZSCHATZ

MEMBER
2006 CHEVROLET COBALT

Engine Mechanical problem
2006 Chevy Cobalt 4 cyl Two Wheel Drive Automatic 60k miles

I have an 06 cobalt, the battery died a few days ago and after I replaced the battery it started and is still missing on two cylinders. Number 1 and number 4. I replaced the spark plugs just in case they was bad, and replaced the boots they connect to. I tryed to start cheap. My check engine light is flashing, and the way I could tell which cylinders it is missing on I took out the new spark plugs and #1 and #4 was not fired at all and had gas on them. Please help!

2 Replies

BRIAN 1

MECHANIC
1,030 POSTS

Try this, Some customers may comment on a severe engine misfire and a SES Light. Upon inspection, DTCs P0300 - P0304 may be found due to misfires on cylinders 1 and 4 or cylinders 2 and 3.

Recommendation/Instructions:
If this concern is encountered, inspect circuits 406 (IC Control for 2/3 Coil) and 423 (IC Control for 1/4 Coil) for an intermittent short to ground or poor connection on either end. Depending on the model, these circuits may short on the AC lines near the AC compressor, on the transmission mount, or on the transmission lines where they enter the transmission. If there is no problem found with these circuits, inspect the ignition control module ground to ensure that it is clean and tight.

If there is no problem found after performing the suggestions above and the diagnostics lead to ignition module replacement, replace the ignition module as directed but also replace all of the spark plugs and clean the ignition module ground to possibly prevent future ignition module damage. Post back with what you find.