Throttle Body Question?

[JDeere7296]

I was inspecting my TB yesterday to see what the TB bypass mod that everyone talks about involved. When I took the intake tube off of the TB I noticed black residue all around the butterfly. I pushed open the butterfly and found the residue all inside the TB and caked in the spiral grooves on the TB spacer that I installed some time ago. I removed the TB and cleaned the spacer and TB with chemtool. I re-assmebled and truck actually has more throttle response. I have never noticed the residue on my 2000 Z-71. Is this normal after only 22,000 miles, and if not what may cause this? Any advice is appreciated.

Thanks,

Andy

[Frank S]

Probably just carbon build up and it's definitely not uncommon to come across.

[99Silver6.0]

The buildup is just about commonplace on these LSx based truck motors. The PCV system in place on our trucks is ill-designed. Oil gets pulled back through the PCV valve and spits it out into the intake manifold. SO, in turn all that crap builds up inside the intake and often times on the injectors! Even makes the TB sticky at times. If you pull off your TB and stick your finger in the intake, rub the inside of it and see what comes out. Its nasty! Oh yea, time to go buy a few cans of SeaFoam!!!! Change over to the fixed orifice PCV valve. That will cut down on the oil cunsumption/build-up quite a bit.

 

12572717 - PCV Valve (fixed orifice type)