(I'm a noob here - so forgive me if my terms are off)
I was driving home from work last nite and my 94 gsr started to knock/tap loudly and arc whenever I shifted gears or gave it gas. I checked the plugs when I got home and the one in the #3 cylinder was burnt to the point that the ground straps were gone. I'm running the Bosch plat 2 so there were 2 ground straps and both were missing. The sliver tip on the other end was also burnt up and the theads were melted and pulled off with the spark plug wire. The threads (in the tip) melting and coming off with the plug wire happened before and I thought it was a defective plug so I bought a new set and replaced all 4. Now it did it again on the same cylinder but worst!!
I swapped out the plug with another and it runs fine now. What can be causing this and what can I do to prevent it from happening again?

 

What mods are done to your car.. Usally when that happens your running really lean and it usally always happens to cylinder #3 since that cylinder get the most air and naturally runs the leanest..

 

thanks for the reply!

it's stock except for a K&N open air filter.

 

Hmm.. I would be willing to guess then that one of your injectors is clogged up or something like that.. How do the other plugs look.. Also how long was it that you changed the plug in that cylinder?

 

the other plugs looked fine - their chamber walls weren't even as black as the #3.
I changed all the plugs about 2 months ago. They were all still good back then - just the tip on #3 came off so I went ahead and replaced all of them.

is there a quick way to check the injector w/o replacing it??

 

No way to check the injector that I know of.. I would just switch them around and try that.. If your running stock injectors you can find them anywhere, in that case I would just replace the one in #3 and see how that fairs out for you..

 

sounds like a good plan.
Thanks tgreaves for all your help - best info I got by far!!!