Project Bulldog. (1988 Diplomat AHB)

The amplifier is for the EGR valve. All cars, trucks, civ or police had them. It's a diaphram valve that takes the weak ported vacuum signal from the carb, and opens to allow manifold vacuum to operate the EGR valve. Think of it like an electrical relay except it's for vacuum. There's also a vacuum solenoid valve next to the amplifier operated by the EGR timer (orange box on firewall).
The hose from manifold to amplifier will cause a semi big vacuum leak if it's broken, and could be noticable at idle.
 
thanks. yep that was all that was wrong.
plugged it up and replaced a few busted hoses and he's running not like total crap!
can actually get up to speed without a huge delay now.
i have two hoses i cannot identify. they come from the firewall emissions stuff.
one looks like it is supposed to go to the EGR Valve but someone has put a hose from that to the manifold vacuum tree by the radiator thermostat.
i could have sworn when i first got the car the three port hose for that tree was there. it's gone now. EGR has no check valve either
IMG_20260803_171312705_HDR.jpg
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The diagram on the top of the fire wall or hood should show where all the hoses were supposed to go.

That thing on the intake with the 3 connections is a vacuum switch that won't let the egr or whatever else is connected work until the engine reaches a certain temperature.
 
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