Okay,

I have a 1994 Trans Am LT1 with Aluminum Heads. I just bought this car like six months ago from a guy. Yesterday, while I was installing my Jet Hot LT Headers and Delteq system I went to change the spark plugs to find a shocking discovory. Apparently, this guy has 2 different brands of spark plugs in there that are 2 different SIZES!! There were about 5 Bosche spark plugs in there with some long threads and about 3 AC Delco plugs with short threads. Well, this was only the first discovory. I went to put my new NBK plugs with long threads in and on the drivers side one did not go in all the way and seat, so I pull it out and it has carbon on it. This is where he had one of the short plugs. So I am thinking that there is a carbon buildup in the spark plug hole. What should I do about this? If you need more information about this to help me assess the problem please ask. It is a long story and I cannot sit here and type all of it out.

Thanks

 

When the piston is down, there is no such issue in putting the plug in. Put in your new plugs, pull your 02's and dump in some Seafoam. But be warned, you will probably waste your cat. Best to unbolt the cat before you proceed.

 

Most automotive stores carry a spark plug hole chaser. Don't forget to apply some grease to the chaser first, that will catch any shavings that might other wise fall into the cylinders.