How to get a diagram to the vacuum hose system of a 1977 cutlass supreme

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Oldsmobile Cutlass Supreme (1993) - fuse box diagram ...

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Jul 25, 2017 - Oldsmobile Cutlass Supreme (1993) - fuse box diagram · Glove Box Fuse Block · Component Center · Passenger Side Underhood Electrical Center · Driver ...

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You should only have 1 vacuum hose that goes from the intake manifold into the evaporator core housing and thru the firewall. It should be easy to check for engine vacuum at the heater control head by taking the control head loose and pulling the vacuum manifold from the back of the switch with the engine running. You should get a very noticeable sucking noise from the manifold. The line that goes thru the firewall is a small 1/8" plastic line that gets brittle over time and is known to crack and break under the hood.

it is in the workshop manual

GM dealership can print you one off from their parts diagram, usually free.

Engine Vacuum Hoses are on a label
under the hood of all vehicles

Fig. 4: Oldsmobile-built 350, 455 V8. Engine firing order: 1-8-4-3-6-5-7-2. Distributor rotation: Counter-clockwise

Hope helps.

You can go to a nearby parts store and purchase a Haynes automotive reference guide and it contains all the different diagrams that would need. On the front of the book it would say 1990-94 lumina cutlass etc.

you did not specify what engine you have so I guessed with the 3.4l

Ok sent you this the engine you have to specify that engine has to help you. Thanks

check all hoses on the engine that dont have water in them for cracks. you can do this by running it up to tempeature and the ones that are hot have water in them.