Help tracking vacuum hoses

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Dec 9, 2020
portland, oregon
I’ve been working on some items in the engine bay and lost track of where some hoses connect. I’m hoping that someone can help confirm the places where I marked as A in the picture are the same hose. Also, there is a hose coming out on the opposite side of the valve I marked as B. Does it go down and connect to a metal nipple that is sitting alone down in the area where I marked as B too? I cannot find a clear diagram of all the hoses. I added a picture of a surprise I found in the air filter housing while replacing the filter. I surprised to see all of that in there. I bought this truck and drive it straight to the shop I rent to work on it, but I noticed there wasn’t much acceleration. This is probably part of the reason.


In this image the ports pictured at the top right are located on the passenger side of the carb and are the 4 lines that run forward to 4 vacuum pipes over the intake in front of the carb. In the image below that, 12 dots represent the metal vacuum pipe ends that face the drivers side fender. The items numbered 1-12 below that tell you where to connect those pipe ends with vacuum lines. B in your image is an EGR modulator valve. Having it disconnected will affect engine performance. This image is from the emissions FSM (you can find in the "Resources" tab at the top of the page if you drill down.) and has detailed info on how to test many emissions components.

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