Chevy Cobalt Forum banner

Status
Not open for further replies.
1 - 13 of 13 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
Like the title says wife's car (05 cobalt LS 2.2L auto) is misfiring (sort of like a sputter at idle. No CEL. Go to hook up my code reader. It powers up but no communication.
Also I pulled intake and throttle body and cleaned (even though it really wasn't dirty).

Not sure where to go from here.
 

·
Registered
Joined
·
949 Posts
Joined in July of 2011 and this is your first post? Wow, professional lurker! :laugh:


I'd probably say check the spark plugs and the coil pack first.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #3
Yea I know. I usually fix the problems using search function :wink2:

I pulled the plugs yesterday they were fine (they only have 20000 on them). They were light gray. Is there a way of testing the cassette type coil pack?

Thx
 

·
Super Moderator
Joined
·
11,821 Posts
You can check for cracks or arc burns but only real way to check the coil pack is to replace it. If it's never been changed chances are it's due.

I believe the key has to be turned to accessory for the PCM to communicate with the OBDII port and the 05-06 is not compatible with Candi module readers.
 

·
Registered
Joined
·
949 Posts
Did you happen to check the plug gap? They've got pretty small tolerances.

I've never had to do it, so I don't know for sure this is a good method, but this is what I got from Googling it:

How to Troubleshoot an Ecotec Ignition Coil
 

·
Registered
Joined
·
125 Posts
You can check for cracks or arc burns but only real way to check the coil pack is to replace it. If it's never been changed chances are it's due.

I believe the key has to be turned to accessory for the PCM to communicate with the OBDII port and the 05-06 is not compatible with Candi module readers.
Is there a timeline on changing them? Or just when they may be a problem? I'm at 173,000 miles on originals.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #7
Ok i'll grab a new one on the way home tonight. Ill also check plug gaps.

Thx for the reply i'll report back with the results.
 

·
Registered
Joined
·
949 Posts
Is there a timeline on changing them? Or just when they may be a problem? I'm at 173,000 miles on originals.
I don't see anything about the coil pack on the Recommended Maintenance Schedule thread. If you're not having a problem, it's probably fine. If there's a misfire, or just rough idle, you might replace them next time you replace your spark plugs.
 

·
Super Moderator
Joined
·
11,821 Posts
Like anything else some last for ever some die prematurely. They have been problematic and are often the cause of erratic misfire and rough idling. As far as gap be very careful with the dual iridium plugs, they come pre-gapped and are easy to damage because of the little iridium piece that's welded to the electrode. ( You can barely see it )

 

·
Registered
Joined
·
125 Posts
I don't see anything about the coil pack on the Recommended Maintenance Schedule thread. If you're not having a problem, it's probably fine. If there's a misfire, or just rough idle, you might replace them next time you replace your spark plugs.
I just put my second set of plugs in at 160,000 miles. Those coil packs are fairly inexpensive, like $26 and change on rockauto. I've noticed a slight stumble or misfire at idle so maybe I'll replace them and see if it helps.

I guess the AC Delco's are the best to get?
 

·
Registered
Joined
·
4 Posts
Discussion Starter #11
So it was either the ignition coil pack or the icm. I didn't want to make another trip to the parts store so I grabbed both. I checked the plug gaps and they were spot on.
Thanks everyone for your help and replies.
 

·
Super Moderator
Joined
·
11,821 Posts
You have an 08, his has a single coil pack for all plugs similar to this.

 
1 - 13 of 13 Posts
Status
Not open for further replies.
Top