I am trying to piece together this puzzle. 86, 4 speed, 3.4 swap, the car was half disassembled when I bought it, I can not figure out where all the vacuum lines go. Theres a rubber hose line off the EGR solenoid, where does that go? Do I need all the purge hose lines to the emissions canister(can I just delete this stupid thing)? Theres a hard vacuum line along the firewall, where does that go? I am not doing the cruise control right now but where does that pick up vacuum from? Any pics of actual vacuum routing and not grainy pics of schematics would be greatly appreciated. Also, where does the brake booster get vacuum from?
[This message has been edited by Filben (edited 04-05-2025).]
I am trying to piece together this puzzle. 86, 4 speed, 3.4 swap, the car was half disassembled when I bought it, I can not figure out where all the vacuum lines go. Theres a rubber hose line off the EGR solenoid, where does that go? Do I need all the purge hose lines to the emissions canister(can I just delete this stupid thing)? Theres a hard vacuum line along the firewall, where does that go? I am not doing the cruise control right now but where does that pick up vacuum from? Any pics of actual vacuum routing and not grainy pics of schematics would be greatly appreciated. Also, where does the brake booster get vacuum from?
everything goes exactly the sane as a stock 2.8l v6 luckily. i have the charcoal canister missing on my v6 fiero and my solution was to just make a purge vent so i didnt have an open hose into the fuel tank or filling the engine bay with fumes the line on the front firewall is for egr stuff thst is no longer used (plug the vent in the air filter can since the fiero goes through the center out) im not sure about cruise as im actually missing mine
the big port is the egr tube thats now unused. the small tube coming off of the air intake tube is for something but its not there anymore on my v6 stuff. the yellow? no idea becuase its not on my v6 stuff unless its coming from the rear valve cover. is it coolant perhaps? edit: wait i might be an idiot. get a betrer picture please so i can see if im a moron
[This message has been edited by cartercarbaficionado (edited 04-05-2025).]
the big port is the egr tube thats now unused. the small tube coming off of the air intake tube is for something but its not there anymore on my v6 stuff. the yellow? no idea becuase its not on my v6 stuff unless its coming from the rear valve cover. is it coolant perhaps? edit: wait i might be an idiot. get a betrer picture please so i can see if im a moron
The yellow is some big metal tube to the back of the throttle body. I have piles of random parts in the garage and that is where that one went I suppose. I have the MAP to fuel pressure regulator. I found the port for the brake booster(its the big one on the back of the intake manifold I think, it was NOT hooked up there when I got the car). I have the PCV valve hooked up. Right now I need the EGR control valve thingy, it has THREE lines from it, two from one end, and one hose from the other.
The yellow is some big metal tube to the back of the throttle body. I have piles of random parts in the garage and that is where that one went I suppose. I have the MAP to fuel pressure regulator. I found the port for the brake booster(its the big one on the back of the intake manifold I think, it was NOT hooked up there when I got the car). I have the PCV valve hooked up. Right now I need the EGR control valve thingy, it has THREE lines from it, two from one end, and one hose from the other.
seems like you got it figured out then. the one end thats smooth on the egr controller can just be left open. the 2 small lines are the important ones. i think my 87 gt had that line litterally plugged onto a stud when i got it
The yellow is the line for the idle air control, it is vital to be hooked up, if it is open, engine will have no idle control and a half inch open vacuum port (it'll rev real high).
Large metal line is the pre recall PCV vent routing (not EGR!), the small rubber hose is connected to a small diameter metal line on the firewall that leads to a rubber hose to the EGR solenoid. The large metal line is unused, the rubber hose should be hooked up, but isn't as vital as the iac line.
The yellow is some big metal tube to the back of the throttle body. I have piles of random parts in the garage and that is where that one went I suppose. I have the MAP to fuel pressure regulator. I found the port for the brake booster(its the big one on the back of the intake manifold I think, it was NOT hooked up there when I got the car). I have the PCV valve hooked up. Right now I need the EGR control valve thingy, it has THREE lines from it, two from one end, and one hose from the other.
Brake booster is the big one on the passenger side of the intake, the rear valve cover PCV valve goes to the large port on the bottom of the intake, the front valve cover PCV goes through a metal tube to the rubber intake just before the throttle body.
The EGR solenoid (black thingy) one line goes to the throttle body switched vacuum (one of the 2 small vacuum connections on the bottom of throttle body), one to the EGR valve (on the exhaust y pipe) and the larger one by itself goes to the small diameter firewall metal tube going to the rubber tube beneath the air filter.
The yellow is the line for the idle air control, it is vital to be hooked up, if it is open, engine will have no idle control and a half inch open vacuum port (it'll rev real high).
Large metal line is the pre recall PCV vent routing (not EGR!), the small rubber hose is connected to a small diameter metal line on the firewall that leads to a rubber hose to the EGR solenoid. The large metal line is unused, the rubber hose should be hooked up, but isn't as vital as the iac line.
Okay, green is hooked up(I found a pipe laying in the parts pile and the hole in the back of the throttle body that matched). Now in the new pic I uploaded, GREEN goes to the small metal line along the firewall and then at the other end I hook that to the EGR valve ?
Originally posted by Filben: Okay, green is hooked up(I found a pipe laying in the parts pile and the hole in the back of the throttle body that matched). Now in the new pic I uploaded, GREEN goes to the small metal line along the firewall and then at the other end I hook that to the EGR valve ?
No, green goes along firewall to the rubber hose you mentioned at the beginning (beneath air filter), blue and red go to throttle body and EGR valve, in that order, blue to rear most port on throttle body, red to EGR valve. The front (bottom) port on the throttle body goes to the dogbone location then across the trunk to the evap canister. The drivers side small port on the intake goes to the dogbone, across the trunk, to the cruise control and evap system.
the big port is the egr tube thats now unused. the small tube coming off of the air intake tube is for something but its not there anymore on my v6 stuff. the yellow? no idea becuase its not on my v6 stuff unless its coming from the rear valve cover. is it coolant perhaps?
The big tube is unused, but it was for the PCV system, not the EGR. The small hose plugged in to the small metal tube that runs with the big metal tube across the firewall, another small hose plugged into the EGR solenoid and supplied vent air.
The yellow port is connected to the tube that comes out of the lower port on throttle body that faces the upper intake. There should be a nipple and some 9/16" hose that connects to the TB tube.
[This message has been edited by olejoedad (edited 04-05-2025).]
No, green goes along firewall to the rubber hose you mentioned at the beginning (beneath air filter), blue and red go to throttle body and EGR valve, in that order, blue to rear most port on throttle body, red to EGR valve. The front (bottom) port on the throttle body goes to the dogbone location then across the trunk to the evap canister. The drivers side small port on the intake goes to the dogbone, across the trunk, to the cruise control and evap system.
Okay, I think I have it all now. I have every line laid out, every port accounted for so hopefully that does it when I stick the engine back in. Thank you everyone!
The small hose plugged in to the small metal tube that runs with the big metal tube across the firewall, another small hose plugged into the EGR solenoid and supplied filtered vent air.
Joe, take a closer look to where that small tube connects to the air filter assembly. Oddly enough, it's prior to the filter.
