OK, I have some pics from my 90, in no particular order. The 3/8 line in the middle comes off the intake mainifold and crosses over behind the valve cover. This is the source vacuum for the HVAC system, cruise control and vac diso axle. More on this one later.
The other 2...far left comes from the CCV...see next pi for where it goes.
The tiny one in the middle goes from the MAP sensor to the throttle body.
this one comes from the CCV in the back of the valve cover and plugs in to the exhaust manifold in front of the throttle body. The other small little elbow goes to the fuel pressure regulator on the fuel rail.
This is the vacuum harness where most of the vac lines for the emissions system all pass through. The big one goes all the way through from the valve cover to the air box...there's 2 ports there, don't know why...only one is hooked up, the two curved ones plug into a double "tower" on the intake manifold and pass through the harness towards the EGR and EGR solenoid. Another goes to the airbox for the thermostatic control (mines deleted).
The one just below the fat one goes to the intake tube in between the two large emissions hoses (it's an aftermarket CARB [California Air Regulatory Board] approved intake. The other one is capped.
Another view
The cylinder thing in the middle is the Fuel Pressure Regulator, it's got it's own dedicated line and ALSO hooks in to the intake manifold via it's own little brass nipple.
This is all the HVAC and cruise mess. I stuck the vacuum reservoir in the firewall after I snapped a couple of lines on the trail...hadn't cleaned it up on picture day. Most notably the pink line is for the heater control valve...deleted...the black line next to it powers the HVAC blend doors.
On the reservoir there is one marked "VAC" or "vacuum" which comes into the ball from the SOURCE, the smaller line goes OUT to the various servos, HVAC, Cruise, Disco axle, disco switch, etc.
After I post this I'll look more closely at the pics and try to explain them a bit better.:gee:
Just for clarity, although this IS a 90 4.0 the cooling system is converted to an open system which is why it looks different. The heater valve is a 91-96 version and the coolant pressure bottle is gone. The pink one is now clipped and capped and the heater valve is gone and all this is cleaned up
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