DK Audio

hey, last week I bought a 97 ES300 and you said to stick my finger in the oil filler cap to check for carbon. Well, tonight I did my first oil change on it using Mobil1 Synthetic 10W-30. I started to scrape it with my finger nail and it was a layer of carbon. The layer wasen't to thick but not exactly really thing either. I got all of it off. When it came off it felt like fine sand. How bad would you say this is? My car has 103,000 miles and I'm kind of concerned now. When you say inside the filler cap you do mean the area where you pour the oil in, right?

flipside909

Whoa...okay wait a minute. That black stuff on that backstop you see when you open up the oil cap is just a coating that's on ALL 1MZ-FE's and the new 3MZ-FE's new and old. Don't scrape it. It was designed that way. You have nothing to worry about.

DK Audio

LOL, ok good! Did I do anything bad by scrapping it then? What is it for?

flipside909

Not really, but just don't scrape it up anymore. I haven't figured out why Toyota put that coating on the backstop. Brand new, the coating actually is solid and doesnt flake up...but as the engine ages and succumbs heat and etc, that coating eventually breaks down.

skperformance

iTrader: (6)

i do not know of any coating ,not saying there is none i personally don't know of any
i did mean to check the inside of the rocker cover where the oil cap goes ( the underside ,inside the engine)
not sure if there is supposed to be a coating on the oil cap
there will always be some residual deposits inside an engine from heat vapour and pressure
some are just really bad and they are caked on
especially with obd 1-and 2 engines which run hotter to conform to higher emmision standards

flipside
what is a back stop?

flipside909

The first thing you see when you look down the oil filler opening. I call it a backstop because oil hits that part first..and basically deflects the oil towards the crankcase.