opti vac hose routing help

[grandkodiak]

96 lt1

There are 2 connections on the opti drivers side, one top, one bottom, for vac hoses...and i have 2 hoses, one with blue/white valves, and one without. i foudn the pic below so i know the one with the blue/white valves connects to the intake manifold by pcv, and thus the other hose connects to the intake tube... but which ones top/bottom on the opti itself?

http://shbox.com/1/opti_vacuum_hose.jpg

ps. there is a vac spit on the intake manifold... where does the other line go? its not pictured on shbox.com, and its too tight back there to follow if with your fingers unless you remove the tcs box and mounts...which im not doing.

[sweetbmxrider]

they are two different sizes so they should only go on one way. you could probably force them on incorrectly, but its nearly impossible to mistake which goes where.

http://shbox.com/ci/opti_vent.jpg

this should explain the other thing :)

http://shbox.com/1/emission_hose_routing.jpg

i believe you are referring to the evap vacuum line. it runs from the passenger side via hard line under the throttle body and to that "split" fitting.

[grandkodiak]

Well my two hoses are already connected to the opti, and are not together... and I have ram air now, but both hose ends are identical in every way. there isnt a plastic adapter on either end now to connect to the intake tube, im going to have to fab one for the ram air.... i just dont know which one to connect where up top. if they are different on the bottom, i dont know because i can reach the bottom one anyway to get it back on if i take it off. (its also an msd opti if its any different...dont think it should be)

anywho, the OTHER vac line is split FROM the place on the manifold that the opti vac tube should connect. instead of a single connector, there is a splitter with 1 hose already on it going back down behind somewhere...?

ill post pics in a few.

[transmaro93]

the one with the little blue valve goes from the intake to the opti and the other goes from the opti to the throttle bellows... i would imagine since its a vacume line taht valve is only going to let in air one way... so blow on in one side and if it doesnt let the air through you know which way its gotta go.. but i do beleieve the shorter hose connected to the valve goes toward the intake... and the longer side goes dist...i could be wrong but i can look tomorrow for you

[grandkodiak]

Heres where 1 hose connects on top of the opti, i didnt put it there, it was there and not connected. this one does NOT have the valves, and has nothing special on it, jsut a length of hose.

http://68.37.131.101/1.jpg


The second hose with the blue valves is currently connected to the bottom of the opti, again, i didnt put it there, and is not connected to anything on top. I put it on the intake manifold just for this pic to show where the split connector is. the opti hose i just throw on the top part of the splitter (marked with red X) but the bottom piece is the other unknown hose that i dont know where it goes. its bent 90 hard plastic then a length of hard plastic to a regular rubber vac line, but then i cant trace where that goes.

http://68.37.131.101/2.jpg






PS Yes the hose with the valves for sure should connect to the intake manifold according to the diagram, but should it connect at the other end to the top or bottom of the opti. thats the q now... that diagram doesnt show it because its stupid, and doesnt differentiate the hoses, but clearly has them merge in a plastic protector that is NOT SEE THROUGH. **** you very much engineering genius@gm.

[transmaro93]

i cant be sure becuase mine were two diff sizes so i didnt really have to think to hard about it but if i remember i will look tomorrow for you when im under there...

[sweetbmxrider]

the hose with the blue valves goes from the intake manifold to the opti body

the other random line, does it run towards the rear of the motor? its most likely for the egr

[grandkodiak]

arg.

**** it, SAT style: Connect the letters A B C and D in the diagram. If you say A to B, and C to D, you fail.

http://68.37.131.101/2b.jpg

[sweetbmxrider]

if C = opti body and D = distributor cap judging by the positions,

B to C
A to D

[LTb1ow]

http://www.shbox.com/1/opti_vacuum_harness.jpg
http://www.shbox.com/1/opti_vacuum_hose.jpg
http://www.shbox.com/1/opti_vacuum_conn.jpg

That should cover it.

[sweetbmxrider]

damn, i was right eh?