What's the black soot like stuff in my throtle body

I just checked my air filter and there was this black stuff in my throttle body.What is it and how do I get rid of it?

It’s most likely from blow-by gasses combined with engine oil. It comes from the PCV system. The PCV system sucks air out of the crankcase and feeds it into the intake, usually at or near the throttle body. A small amount can be normal. An excessive amount can be due to worn out rings on a well used engine.
You can use a throttle body safe cleaner to clean it off. Avoid getting chunks of it ingested by the engine.

should I change the Pcv valve? would it help to do anything else?

The soot accumulates in the throttle body from the PCV and the EGR gasses that are reintroduced into the intake system. There’s really nothing that can be done to prevent this. Just make it a habit to clean the throttle body each time the air filter is replaced.


The EGR system was the first thing that came to my mind also.

The black stuff is carbon. It’s left over from the combustion process, is normal, and is fed in small amounts into the intake with the exhaust gasses via the Exhaust Gas Recirculation (EGR) system when you punch the throttle. The exhaust gas is fed back in there in small amounts to displace a bit of the incoming oxygen to keep the cylinders from getting too hot. This is done to prevent excess NOx from being produced and to prevent preignition.

I guess that all depends on the OP’s definition of “black stuff.” I assumed oily black stuff, and you assumed sooty black stuff. Either or both could be right.

True. Oily black stuff would be carbon wetted by fumes from the crankcase.

checking the function of the PCV is one of the simplest jobs you can do on any engine.
It is nothing but a mechanical check valve. If it is clogged it wont pass air either way, so it should be replaced. If it is not clogged or sticky, it will pass air only one way, in the direction of the arrow on its side. So you can test it if you want to, but dont replace it unless if is bad. If it is clogged, or sticky you can often clean it with simple green and put it back in working condition.