: Bad coil packs or what?

03-08-06, 07:09 PM
Ok heres my newest problem on my 4.0 Aurora V8 with 92k miles. 2 days ago went out and started the engine and let it idle about 5 min while i run inside. After i started driving immediately knew something wasnt right. It was sputtering, running real rough and smoke was pouring out of the hood and catalytic converter. It felt like bad plug wires did (my originals did the same minus the smokey stuff). I looked uner the hood and the smoke appeared to be pouring directly out of the coil pack area (4 black ones on the back of the motor).

I dropped the damn thing off all day yesterday at my northstar mechanic guy, and someone new apparently worked on the car. First off they didnt even call me or nothing and tell me what was wrong before they did the work. And when I got there they said the plug wires were freyed (I just put them on 15k ago, how the **** could they be arching now?) That couldnt be..and they changed 1 coil pack, whichever one they though was bad. Okay, now fast forward to tonight I pick it up, pay the damn $400 bill on my discover, then happen immediately notice it was doing something similar. I found out they put Borg Warner plug wires on, so I went back and told them I want it switched to ACdelco set for nothing. So Im dropping it off thurs for that and hopefully fix everything and not pay a dime more.

This sucsk though. The day before it was running as smooth as can be and I loved it. Anyone have any ideas for me or did I hit it right that it is the coil packs?

03-08-06, 07:32 PM
coil packs + smoke = bad

You can get whole ignition modules+coils for like $40 at the junkyard. If it's still running rough after that work, then they didn't fix the problem. It could still be another coil or the ignition module itself.

03-08-06, 07:48 PM
Yeah, if you replaced the wires only 15k ago and it were AC Delco, I find it hard to believe its gone bad already….unless it got fried when this event happened.

Also, if the smoke was coming from the coil packs, then that’s probably where the problem is.
Its very easy to check to see which on is bad. (do a search here, I posted step by step)
If not, autozone has a step by step in their book behind the counter. (real simple, just measure the resistance across the terminals and see which one is reading way different from the rest)
A coilpack costs less than $20 each, on only held on by 2 bolts.
It so simple to replace since its sitting right on the top of the engine, I replaced mine in the autozone parking lot in less than 5 minutes.

I'd just buy new ones rather than roll the dice on junkyard parts. I think they have a tendency of going bad around the 80-100K mile mark. (that’s when I lost 2 of mine, one at 80K, the other around 90K)

There was no smoke though….

03-08-06, 11:32 PM
Thanks. I also forgot to mention it threw a misfire code and the idiot light never came on again for the shop. As soon as I pull into the garage it illuminated. It also didnt do any of the crap for the guy either, probably just karma for me beating it when I first got it.

I will get them to trade for the delco plugs and try to get them to replace all the coil packs for nothing. If he wont do that, i guess I'll have to write a letter to the CC company. I hate to burn the bridges with this guy though, he is really good (built a 6k engine for my friends 94 T/A, that thing is MEAN). I saw cases of beer sitting there too, wonder when they drink those.

Anyway, yeah I never seen the smoke coming out like that before or even heard of it. Maybe its the coolant inside the coil pack thats shot, and it overheated or something and is burning that off. But the smoke was also literallly pouring out of the catalyst. That's something I havent seen b4 either. Is that just motor oil getting in there and being burned off? It didnt smell like eggs, more like roasted pork. whatever.

I figured the coil packs would be shot among a few other things around this mark. I hate how this happens right after I buy a $400 security system though, thats BS.

03-09-06, 02:28 AM
See, coils (actually all electronics) run on smoke, that smoke is inside of them at all times. When that smoke escapes, they'll no longer work, because there is no more smoke inside them. It's called the "positive smoke test" according to my old electronics teacher.

03-10-06, 02:59 PM
I hate how this happens right after I buy a $400 security system though, thats BS.

Aurora, not for nothing but that could have something to do with it. I got the Viper791XVw/ autostart on mine.. I noticed a wire of it runs to the coil pack area, I guess this is how u can autostart it without the security system freaking. Anyway, a bunch of autostarts later I burnt a coil and a while after that I burnt another... its worth looking into.

03-10-06, 11:21 PM
Well, I sent back the viper system i bought. I have the Crime Guard system from crutchfield. I sent back the $420 viper unit (this fiasco happened after i bought it, but not installed). I actualy just got the car fixed yesterday, and had the Crime Guard 850i installed today. It was half the price of that. The viper is better but this is still pretty good. the motion sensors and everything is sweet. I like the chirp chirp on lock too,. Anyway. at least the autostart works like a champ. I'll see if it messes with the coils again. There is a newish looking black wire going into it now, so that must be it then.