'07 Scion tC looks like burnt intake valves?

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When my buddy and I installed an aftermarket header a couple months ago we noticed the intake valves were white on the header side and it looks like some kind of deposit build up is there. Has anyone ever ran into this issue and found a good way to solve it without taking the engine apart? Usually when I see dirty intake valves they are black.

Status on vehicle:
- I do a lot of short trips because I don't live far from the base and did a lot of short intervals driving to different buildings within a couple of miles.
- Highway driving is usually less than 10 minutes a day because there is no need for me to be on there.
- I have a short ram intake that I've been running since 15,000 miles and car currently has 97,000.
- Valve cover gasket is leaking a little bit and I just switched to Valvoline FS w/Max Life 0W-20 because of the bad piston design and seals are probably old by now. (There's a TSB for oil consumption on these vehicles)

So yeah I'm just pretty curious if anyone has ever ran into thi before.
 
Intake valves do not burn

That picture does not show a burned valve (at least you can’t see if it is burned)

You can’t fix a burned valve without removing it
 
Originally Posted By: crazy_raccoon
When my buddy and I installed an aftermarket header a couple months ago we noticed the intake valves were white on the header side...


You can't generally see the intake valves from the "header side". Those look like normal exhaust valves.
 
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A bit white to me, but not terrible. I'd like to see tan instead ... Only a tuner chip with a slight increase in air/fuel ratio will get there ...

The changes you are making are likely leaning it out some. The ECU is not compensating ...
 
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Unless the engine has both manifolds on the same side, which is uncommon in more recent decades as it's less efficient, you're looking at the exhaust valves and unless you have a misfire your valves aren't burned. That's probably just a sign of a good clean burn.

When a valve burns, is when part of the shoulder (where it contacts the seat) begins eroding giving combustion gasses a route to escape and compression loss is the result. Intake valves are exposed to cooler air and gasoline (except in DI) passing over them so run cool enough that they almost never burn.
 
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Originally Posted By: SubLGT
Originally Posted By: crazy_raccoon
When my buddy and I installed an aftermarket header a couple months ago we noticed the intake valves were white on the header side...


You can't generally see the intake valves from the "header side". Those look like normal exhaust valves.


Yep - those are "Normal" EXHAUST valves, yo.... dude
 
2 things of note:

(1) the picture showed seems to be the exhaust port (exhaust valves), not intake.

(2) when in doubt: always perform compression checks.

Q.
 
Will resonate with everyone here. Those look like perfectly normal exhaust valves for a 2az engine. We have had a few of these apart and they looked similar. No issue to report on your car.
 
Sorry my mistake. I meant to say exhaust valves as they are on the header side and not the intake side. I wasn't sure if that was normal on the 2AZ-FE motor that's why I wanted to ask. Thanks everyone even with the sarcastic reaponses. You live and learn.
 
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