Vaccum guide - 1987 Toyota Supra

Possible faulty carb. 2bbl or 4bbl? 360 engine? Make sure that the base gasket is not leaking vacuum. The dist should have venturi vacuum.
https://www.autozone.com/diy/repair-guides/chrysler-full-size-vans-1967-1988-repair-guide-vacuum-diagrams-repair-guide-p-0900c1528007fbe2

Here's a link Martin to your vacuum lines. Repair Guides Vacuum Diagrams Vacuum Diagrams AutoZone com

Hi Zeb,here's a link to a Autozone repair guide showing you your vacuum diagram. Repair Guides Vacuum Diagrams Vacuum Diagrams AutoZone com

Hi Roman,here's a Autozone link to your vacuum diagram. Repair Guides Component Locations 3 0l vq30de V6 Engine AutoZone com

if it is 4wd check the vaccum lines for the presence of atf, if so you need new ac vaccum lines, ac actuators, vaccum resivoirs, possibly a control head and a vaccum switch on the transfer case and top off the t case, if no atf found check supply vaccum on the black line on the drivside floor area, you have a supply vaccum problem where the break is you have to find, chek the vaccuum resivoir on the driver fender area

go to autozone.com, become a member(completely free and safe) and then you can access their repair guide section which contains a vacuum diagram for your 'bird....you'll use that site a lot.....need to get yourself a haynes manual for your car-.....thanks for the question...ps- also check out a forum just for firebirds....hope this helps

Should be a vaccum routing guide decal in the engine compartment either on the radiator support or underside of the hood. Check a haynes or chilton repair manual.

More them likely you have a vaccum leak, check vaccum line that gose into fire wall under hood make sure it has vaccum, if don't find vaccum hose and repair, if it does check vaccum hose under dash follow it make sure it's plug in, if it is could be a bad vaccum pull off or bend door or the selector switch. Good luck hope this was helpful.

The floor usally has a vaccum servo,so check it to see if the servo is moving.Pull the ac/heater control from dash,and remove the vaccum plug.Spray some silicone(silicone spray only)in the vaccum lines(plug)and the receptical for the plug.Do this while it is on,and engine running,this will unstick the vaccum switch if it is stuck.Also before starting this,check for vaccum at this vaccum switch.If there is no vaccum,go under hood and follow the vaccum comming out of firewall,and find a vaccum reservoir,or a vaccum check valve,and check them to see if they are damaged or not connected.I hope this helps,if you need more help let me know.

go to autozone.com and click on repair guide, there hsould be instructions and a diagram there.