I have about 20k on them so far. I checked one, and according to pictures its perfectly normal. For the first 10k, it was running with out an O2 sensor, AND they aren't gapped correctly.

Should I take the old ones out and just regap them? Or put the new ones in? (I have them already on hand).

Any advice is greatly appreciated.

 

If the old plugs are still good then just regap all of them and keep using them. But if they look worn then replace all of them. It would also be a good idea to hook up the 02 sensor.

 

Thanks for your response. I was going to just regap them, but upon closer inspection, they looked pretty worn. I went with NGK G-Powers.

The O2 sensor is hooked up. I had a custom exhaust done, a long time ago and couldn't afford a O2 then.

 

So I replaced the spark plugs, gapped them at .032, changed the air filter, added transmission fluid, and added manual hubs.

Now I'm getting worse MPG, and no longer do I go 82 at 3,400 RPM, I go 80. What gives? It seems like .040 gapping worked better!

Any ideas?