1989 Camry 4 cylinder spark plugs
 

Hi,

How often should I change spark plugs?

Should I just use the regular/copper plugs, or should i use platinum or iridium?

thanks!!!!!

Suggest Denso brand platinum. Platinum can last 100K miles. The extra cost of platinum plugs is minimal verses copper and they last a lot longer.

Thanks. Do platinums need to be re-gapped?

I use about 1/2 quart every 1,000-2,000 miles. There is no change in mileage or check engine light on. I just checked the exhaust and there is no smoke.

However, I just regapped my spark plugs, #1 and #3 threads have fresh oil. What does that mean?

Depends on what the manufactured plug is gaped at. If gaping only move the ground electrode and don't apply pressure on the center electrode. Use a gaping tool.

Most owners never gap a plug.

The threads of 1 and 3 have motor oil on them?

Use a flash light and check for motor oil getting into the spark plug tubes. The tube is pressed or screwed into the head and can leak.

Unless there is a lot of oil in the tube as in getting onto the spark plug socket, would not be concerned.