Rough Idle - open vacuum line -
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From: Drums Pa
Rough Idle - open vacuum line -
Have an 87 coupe. I decided to clean my TB, first timer. Removal went ok, I only broke a solid/brittle vacuum line. Once removed to my suprise, underneath was an open ended vacuum line. There is no obvious connection to anything.
Tracing it to the source it connects to a strange little apparatus.
1) Located: under right front of plenum, just behind TB.
2) Discription: two tiers, upper section has two wires and the lower section has two solid pieces of vacuum line. The wires come from a wiring harness that follows the plenum rail.
3) Destination: one lead goes to the cylindrical device located under the plenum entering the middle of the engine. The other WELL THATS what I need to find out. Out of the connector both ends are made of a solid 1/8 " tub. The one that is open transforms to a 4" piece of flex tubing, for what thats worth. Help !! I can send pick if it helps..Charlie
Tracing it to the source it connects to a strange little apparatus.
1) Located: under right front of plenum, just behind TB.
2) Discription: two tiers, upper section has two wires and the lower section has two solid pieces of vacuum line. The wires come from a wiring harness that follows the plenum rail.
3) Destination: one lead goes to the cylindrical device located under the plenum entering the middle of the engine. The other WELL THATS what I need to find out. Out of the connector both ends are made of a solid 1/8 " tub. The one that is open transforms to a 4" piece of flex tubing, for what thats worth. Help !! I can send pick if it helps..Charlie
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From: Yucaipa CA
That's your EGR control. The one tube goes to your EGR valve under your plenum. The other "open" line should run to your front left headligt well and connect to a vacuum line near your vacuum canister.
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From: Drums Pa
Originally Posted by cash's90
That's your EGR control. The one tube goes to your EGR valve under your plenum. The other "open" line should run to your front left headligt well and connect to a vacuum line near your vacuum canister.
The open-line almost looks like it is designed to go into the bottom of the TB, however I disconnected a different hose from that. What a minute let me look...
I just looked at the hose I disconnected from the base of the TB, it is (T) tapped into the same v-line you discribed as going to the front left headligt well. It is
Wait a minute, does the line that runs to your front left headlight have a T-connector about 5" 's from the connector, or is it a home run.
Anddd do you know if the rear of this connector loops to the driver side bottom of your TB ????
Le Mans Master
Joined: Feb 2000
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From: Kempner Texas
The underside of the TB on the driver's side has a vacuum bib that works with the fuel tank venting cannister arrangment located in the well below the driver's side headlight.
I removed my EGR stuff so long ago I can't recall all the 'T' and solenoid connections.
Jake
I removed my EGR stuff so long ago I can't recall all the 'T' and solenoid connections.
Jake
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From: Drums Pa
Originally Posted by cash's90
My EGR solenoid only has 2 vacuum lines. One in from the vacuum source. One out to the EGR valve.
Charlie
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From: Drums Pa
Originally Posted by Wayne88
I forgot, there should be a chart on top of your radiator showing the vacuum lines -if its the original radiator. 
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Joined: Jan 2004
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From: Bergen County, NJ
Originally Posted by georgechuckus
Found the chart. Discovered the way I disconnected the TB is the way it goes back together. However my EGR solenoid has two vacuum lines in the front and one in the rear and it is still stranded. The chart on the radiator does not show it. FRIG..
Look at # 18 on the 1st chart I posted. I think this is what you broke.
I'm wondering, does it look like this:It attaches to the EGR Selenoid, 2 hoses, one to the TB, the other to the vacuum canister line. Another curves around to the EGR Valve.
Last edited by Wayne88; Mar 12, 2005 at 10:44 PM.
Drifting
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From: CALGARY ab
Originally Posted by georgechuckus
Found the chart. Discovered the way I disconnected the TB is the way it goes back together. However my EGR solenoid has two vacuum lines in the front and one in the rear and it is still stranded. The chart on the radiator does not show it. FRIG..
i think that what its suppose to look like...i remove all the egr stuff including that particular line..threw the fuel vapour tank out as well . plugged off all lines to the tank. my venting is now done through the gas cap..
Last edited by korvette4u; Mar 13, 2005 at 12:25 AM.
Le Mans Master
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From: Kempner Texas
Originally Posted by georgechuckus
Under the throttle body (drivers side) there is a 1/8 vacuum hose connection, where does that hose go to?
Charlie
Charlie
Jake
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From: Drums Pa
Originally Posted by korvette4u
try this link for routing vacuum lines:http://forums.corvetteforum.com/show...hlight=agent86
i think that what its suppose to look like...i remove all the egr stuff including that particular line..threw the fuel vapour tank out as well . plugged off all lines to the tank. my venting is now done through the gas cap..
i think that what its suppose to look like...i remove all the egr stuff including that particular line..threw the fuel vapour tank out as well . plugged off all lines to the tank. my venting is now done through the gas cap..
My vacuum line set up is/was correct as compared to the diagram/s. However the egr solenoid on my car does not match the diagram, as it has a rear vac line comming off the back of the solenoid in addition to the front two v-lines...
Thanks for the link though!!
Still searching !!!! I would love to have it back together today , help...
