Spark plug cover bolt snapped in half.
 

I just changed out my spark plugs and was tightening down bolts that hold the ignition coils in place with an air ratchet. First 3 went on with no problem, but then of course, the last one snapped. If you're not familiar, they are lag bolts that are about 2 inches long and pretty skinny. The threaded part that snapped off and is stuck inside the engine is pretty far down that hole, so I don't really see a typical screw extractor being able to get it out. On top of that the female threads are 100% covered by the snapped bolt, so I can't just use a shorter bolt to fix it.

Anyone have any recommendations on how to get that out? Obviously having the coil just loosely sitting there isn't doing any good. Any help appreciated.

Not to be a dick, but why on earth would you use an air ratchet for bolts that have such a low torque rating? Go to your local auto store and let them know what happened they'll hook you up with the reverse threaded bits.

Well first off, why in the heck would u use an air rachet to tighten those? 89 inch pounds, it's like a little more than hand tight basically. Don't do that anymore lol. U said it broke off deep in the hole, but then u said the threads are covered so u can't get a smaller one in? I'm not getting this, is it broke in 2 places or what? Can u not take out the snapped bolt? Then go down there with a skinny flat screw driver or pick and try turning it out, 2 skinny screw drivers will work, if it's snapped off there is nothing really holding it tight in there so the snapped off threads should be loose and turn easy, just real awkward to do. I did that once on a cam bolt, read specs wrong, used 2 picks to get it out.

X2 on the "why did you use an air ratchet. . ." comment.

But moving on, you can take it to a machine shop. They should be able to tack weld a bolt onto the one that's sheered off and extract it that way. Otherwise I'd suggest buying a used valve cover, not worth the time and money to extract it yourself. $30 get's you a used 2.2 L61 cover on eBay.

2005 2006 Chevrolet Cobalt Valve Cover | eBay

Admittedly I thought about that, but didn't think my air ratchet put down enough torque to break them. I came across a left hand drill bit set that I'm going to try out. I'd be a very happy camper if it pulled the bolt out, because otherwise it'll be a major pain in the ass. I appreciate the input.

Yeah, you could probably save yourself some time and go with a used replacement. Please don't use the air ratchet on that valve cover. I don't recall any of the bolts on there needing that much torque.

I didn't think there was a blueberries chance in hell this would work, but it did! Luckily the threads weren't rusted.

I now know not to use an air ratchet on any skinny bolts. From what I now understand, an impact is a better choice for that application.

Just kidding...

Thanks guys!

Damn, glad you got it out. Ive had a bolt snap in a strut mount and someone cross thread a spark plug in a head. Neither one took less than an hour and a bit of wd-40 and heat to get them out. Oh well right? You make mistakes and you learn.

haha, no way did that work. lol I figured it actually would just maybe take a while because its deep in the threads

also it cant rust, the bolts and the holes are aluminum.

glad it worked for ya thumbs up

These weren't even valve cover bolts, this was for the plastic coil pack that sits over all the spark plugs on the L61.
Wow. I have yet to have an extractor set pull anything out for me, usually manage to break them off and make extraction more difficult.

Same. Had shocks on a jeep rusted in and the bolt broke off. extractor set also broke trying to remove said bolt. had to let the garage do it. good for you though man, glad you were able to get it. don't feel too bad, i used my impact on my o2 sensor because i got impatient because it wouldn't budge no matter what and practically shattered it.

Anytime ive tried to extract anything ive used a combo of wd40 and a blow torch, or heat gun, and had no problems. Just takes a lot of patience. You cant just strong arm it. You have to apply pressure slowly and a little at a time.

i was using a drill extractor where it was supposed to make threads inside the bolt to screw the second bit into the stuck bolt and pull it out

Yeah I have that type and I also have the fluted type.