I know some vehicles like specific spark plugs, not looking for anything exotic nor long wearing.
If regular coppers are right, that is what I am looking for, not what the kid at the parts counter (or the crafty computer) wants to recommend.
This car is eventually going to be in a TEXT and Total accident as the chick can't seem to pay attention nor allow adequate following distance... so nothing too expensive like platinum, rhodium, unobtanium *unless it really needs it...

I looked at the sticky's and did a cursory search and nothing popped out at me
I am new and just starting to learn this vehicle, this web forum, all of ya'll, and all of it's plastic fender quirks...
Cheers!

 

If it is a 2.2, AC Delco 41105
If it is a 2.4, AC Delco 41103

Iridium and not my fault.

Per RockAuto.com these are listed as GM original equipment

 

Thank you, I had already let guy sell me a four pack of Autolites.
Autolite APP5263 (41-981 AC DELCO removed)
Hoping a spark is a spark...

I have the 0300 fault (multiple misfires) and as you can imagine, the car runs like crap (intermittently)
it is the 2.2 engine

How susceptible are these cars to ignition coil pack failure or fault?
[SPARK] * [COMPRESSION] * [FUEL]

I am not a parts tosser, but I am lazy, old, and I started somewhere...and she appeared overdue for sparks. Color didn't seem to be too telling.
Autel Maxisys (pro tablet scanner) live data is looking more like cylinder 4

I purchased a coil pack from the You Pull yard ($23) and installed it when I changed the plugs I will put the other (likely original) coil back in and see if the misfire moves to a different cylinder

if not, it is maybe fuel injector or compression (sticky valve)

 

Oh, sugar
I see that ACD 41105 was not originally installed rather ACD 41981 and I put the Autolite equivalent (of the 41981 in

If'n it got teats or tires... I'm bound to have trouble with it.

 

Put the stock plugs in and go from there
There's a reason that particular plug specified for that engine.

Do you know what else runs like poopy with autolite plugs derived from an interchange/compatibility table? A 2004 BMW 322i.

 

Pull the plugs and check the color of the spark on each plug. You SHOULD have a nice, blue-white spark. If it's yellow-orange, then the coil replacement should take care of that. If it IS already blue-white, then put them back in and do a compression test on cylinder #4. IDK what it should be, but derf probably does. You may have a burnt or sticky valve.

 

Icms were common enough that I kept a spare with my in my 03.
Still have a pile of them.
My 03 base and my 06 redline hated any plugs that weren't AC Delco or ngk. Not sure who made the delcos at the time. But Bosch and autolite were a no go.
I'd probably run a good fuel cleaner through it, clean the throttle body, maybe even an induction service, do an engine flush, and see where it sits from there.
Being it's a 0300, I'd guess the icm or fueling pressure.
Also, a new fuel filter wouldn't hurt. They are serviceable out of the tank.

 

Number 4 misfire is the common coil pack failure. Turn one over and the reason will be clear. The coil pack has trouble sometimes to identify which cylinder is misfiring. The cam position sensor is implied by coil output voltage or something like that.

 

MERGED W EXISTING THREAD

PLEASE KEEP YOUR **** TOGETHER

My misfire has seemingly been corrected...
... not by sparkplugs nor ignition coil
... not by fuel injectors

wait for it

...oil change
Ugg, I believe that the oil or lack of changing, or snake oil, or who knows what...
I think it was making a #4 valve that would occasionally hang open.

I cleaned and tested the fuel injectors (TEMU injector trigger device, and carb/TB cleaner in hose with 40 PSI shop air)
I monkeyed with the coil and spark plugs. It was finally running right, no CEL
Took it for 40 mile drive and on the way back it started acting up again.
Engine was hot and oil/filter change was on my list.
Since then it has been running/working fine? More driving performance test soon to be performed...

Suggestions (anyone) for oil additive like MMO or SeaFoam or STP or DOT3 or ATF or Avocado oil (Californians) (non carcinogenic)
I never actually witness or confirmed sticky valve, just my best educated 'guess'...

 

I don't like to guess I like to test. You may do a bunch of work trying to fix a valve when it's not a valve problem at all. To verify do a running compression test and report back.