Spark plug questions

[ThePlowman]

1993 300zx tt Bad spark plugs. Going to replace them but scared the new ones will mess up again. Could it be possible?
http://postimg.org/image/oyl5leku7/833283a8/

[RubyRed300ZX]

Your post is missing a few details. How long have those plugs been in the car (mileage). They're NGK but what is the number (as in heat range).

[ThePlowman]

Engine has around 60k miles on it, and idk if previous owner ever changed them out or not. I left the spark plugs out side and mom decided to chunk them in a neighborhood dumpster so i cant get the codes off.

[RubyRed300ZX]

They look like they have 60,000 miles of running rich. And you shouldn't run plugs for 60,000 miles in my opinion. Change them out at 45,000 miles or no more than 3 or 4 years at the most so they don't corrode into the heads. Back to your issue though, you have no idea how long they've been in the engine. I'd check codes and check the O2 sensor signals just for the hell of it. Replace them with the correct NGK and call it a day. Clearly you are running rich though. What do the air filters look like?

[RubyRed300ZX]

My post above, the last line was kind of cryptic. Suggestion to check the air filter(s) was to say that if those are filthy then the previous owner wasn't very rigorous on routine maintenance. Thus, those plugs you pulled out have probably been in there for the full 60,000 miles, along with O2 sensors, PCV valves, belts and the timing belt, thermostat, water pump, coolant temp sensor, fuel temp sensor, Mass Airflow sensor etc.

[DCaff300ZX]

+1 to correct heat range OEM spark plugs to be sure, and a call to look for any maintenance needs such as new filters everywhere, and a check of the injector and PTU connectors for corrosion, as well as the CTS...these all will contribute in one way or another to rich running and fouled plugs.

[ThePlowman]

Thanks yall, yes I have replaces the O2 sensor and have cleaned the MAF so I think ima go ahead and throw in some spark plugs and see how she runs

[ThePlowman]

and i think your right about the guy before, I plan on getting all new fluids as well after i see if this will keep her started.

[RED_DET]

Twin turbo plugs, NGK NGK PFR6B-11B
Plug Gap Settings:

0.044" - Stock
0.035" - 15psi
0.031" - 18psi