So the car did not have the original AC Delco 102's but Autolite plugs.
I do not know why people do this since the AC Delco plugs are excellent and do not need to be changed.
Glad the dealer figure it out and TomatoSoup is correct about the CAT been fine.
Agree. Nothing wrong with AC delco. But, are the AC's platinum at both tips? Maybe the former owner swapped thinking he'd have plugs that would last a LOOONNNG time and give greater performance. Personally I don't like them since they last a long time, but generally are not as conductive as a standard copper plug, so no real performance improvement, and they are 3x's the price.
Edit: This is from Oreilly's website about the Autolite dbl platinum APP5263, "Platinum is one of the most durable metals used in spark plug tips today. Due to its durability, it virtually eliminates gap erosion and lasts longer than standard plugs. Autolite® Double Platinum Spark Plugs feature: Original OE design. Platinum to platinum firing. 30% more durable. Maintains optimal performance longer. Virtually no gap erosion. Nickel-plated threads and shell. Top fuel efficiency over the life of the plug."
$4.49 ea. but if you read what it says, it never says increased performance, only that you will get peak (stock) performance and fuel efficiency over a longer period before needing replacement. they are supposed to be gapped at .044
They also sell an iridium autolite for $6.99, again only touting long life and premium performance over that time, NOT increased performance. again gap is .044
They also sell an AC Delco iridium plug for $7.99
Edit: interesting, this plugs part number is 41-108, and the gap is .035, that is what is supposed to be stock in my car, so that's an iridium AC Delco plug, wonder why autolite opened there gap? And why would someone replace a more expensive iridium plug with a dbl. platinum?
Oh, and this search was for my '09 GXP
'09 Solstice GXP Coupe #492, Mysterious, Auto, 6473 miles.
DDM Venom Brace
DDM 3/8 Performance backbone
DDM Catch can, Tclamps and fender trim kit.
GM Accessories incl. race pedals, rocker panel clear protective tape, console storage bag, and soft targa top.
'95 Bronco, owned 20yrs, totally custom on 37's, my DD
'11 Subaru Forrester, wifes DD.