Chevrolet Repair: Spark Plugs

Question
Hi. I have a 1992 Buick Century Special with a 3.3 engine. The parts store says that my car calls for AC Delco R44LTS6 spark plugs. I put in a set of these and my car didn't run very good. So I put in a set of AC DELCO R45LTS6 spark plugs that my 1990 Buick Century Custom 3.3 uses and my '92 model ran much better. Now my '92 Century has developed an intermittent skip that will last for a few seconds and then smooth out and then skip on one plug or wire or something for a short distance and then smooth out again. My question is, what do you think is causing this to happen? What is the best way of checking what's going wrong? Do you think a hotter plug will be better? I found AC DElCO platinum plugs 41-902 on Amazon.com for $2.84 each. Is this a better or hotter plug than the AC DElco R45LTS6 I'm using now. What do you think I should do and is there a possibility a fuel injector is going bad? If so, how do I check to find which one it is? I thank you for you advice and suggestions or any help you may give very much since they don't have a Buick expert available.  Stephen

Answer
Hi Stephen,
The plug you switched to is one step hotter. While running, using insulated gloves and a spark plug wire puller, pull one plug at a time. Same with the injectors. If the engine changes thenbit is fine. But if you unplug one that then engine doesn't change that is the one that is bad.
Good luck. Jeff.