Hey,
Finally I replaced the spark plugs in my 92 SC300. It took me a couple of days, but it can be easily done in one day. Its really not that hard, except for getting off and putting back on that big hose under the throttle body. I also went through and cleaned the throttle body. I used Denso Platinum Spark Plugs ($5.99 each). I cant really say that I feel a difference in the performance, but I wasnt expecting much. Anyways, if anyone has questions about the repacment I'll be more than glad to answer them. LATER.

 

Gold, I'm glad to hear the spark plugs aren't a problem to change by ourselves. I just picked up a 93 SC300 and started doing the basic changes such as oil and filter, air filter, coolant, and gear oil. I'm gonna save the spark plugs until it gets alittle warmer.

I had a 94 3000GT VR-4 and changing the spark plugs cost me $150. Insane!

My dad had a 87 Supra Turbo and I think the spark plugs were a ***** to change also.

 

Congrats

mind writing up an faq for the list, if you got free time that is

 

thats strange, what big hose are you referring to? I didn't have to remove any hoses.. Took about an hour... most of the time went into unscrewing/screwing the plastic pieces.

 

duh! nm you have a sc300....

 

If you're going to replace old plugs, try Torquemaster plugs. I hear they produce the *MOST* difference out of them all. Of course I don't have any data to support this claim other than about a half a dozen personal testimonials, but it doesn't hurt to try something that worked well for many others .

 

I love you lexus guys, starting a new thread because you changed your spark plugs!

No just kidding, I don't know about n/a cars, but with my turbo engine I have had good luck with expensive iridium plugs. My engine will foul most copper plugs after a few months, but iridiums seem to last 3-4 times longer.
Plus iridium plugs have been known to give decent power increases with forced induction engines. Platinum plugs can kiss my *** Tried those for one day, never again.

I found these NGK iridiums at my local parts store, I got them on sale for $23CAD a pair. so I paid $46CAD for the set of 4, which is fairly pricey, but I think worth it....

 

Before starting the spark plug replacment, I looked into all of the possible spark plugs. I was told that the original plugs work best. Anyways, whats really strange is that when I pulled the old plugs out I noticed that they were NIPPODENSO PK20R11. Now in the owners manual, and repair manual it states that the PK20R11 plugs are for the SC400. The plugs should have been PK16R11. The guy who had the car before never replaced them, so they were mixed up at the factory? Could thus have caused any damage to the engine?

 

i doubt there would be damage,
maybe just not optimized for the most power and/or fuel economy, thats prolly about it

the difference between the PK20R11 and PK16R11
prolly is negiable

 

Spoken like a man who has never changed the plugs in a normally aspirated SC300!