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L67 vacuum routing HELP!

thunder71173

SLP, GTP or call it MUT!
Does anyone have a pic of how there vacuum lines are ran. I just swapped in my l67 and it came bare so I had no Idea how to run them especially to the bbv. Any help would be greatly appreciated
 


vacuum.jpg
 
that's a 96/97 routing. 98+ is slightly different as it does not have the vacuum tree by the TB. Therefore the line from the lim comes around to the fpr and BCS as well.
 
that's a 96/97 routing. 98+ is slightly different as it does not have the vacuum tree by the TB. Therefore the line from the lim comes around to the fpr and BCS as well.
Mine is an 03, its exactly as pictured. Is this the tree you're talking about? (top circle)

bbv-1.jpg
 
The vacuum/boost source on the 98+ blowers is non existent minus the cap on the top.

For 98+ blowers you've gotta take it from the LIM.
 


In the black circle is the "tree" that BillBoost is referring to which is only on the 97...in 98 they did away with this "tree" but the vacuum diagram Keithgtp03 provided is for a 97 l67 setup with said tree.
That is a picture of my 03
 
Nevermind...I see what yall are talkin about. Mine goes from the solenoid to the FPS as well. So just skip the manifold vacuum source #9
 
I dont have any evap stuff, i had it deleted so i run a T out of the lim to the map sensor and fpr then another T from th fpr to the bbv sulenoid throught the sulenoid to the bbv valve out of the bbv tho the tree on the sc. the other two ports go to the break booster and the ac controls and i block the port on the throttle body is this right? if so I got it and thank you all very much for the help
 


I got it all routed correctly and it runs great with the exception of a header leak where the primarys come together on the front header. It doesnt push nearly as much boost as I thought it would with the 3.4 could I have a bad bbv valve?
 
its possible that it could be bad...yes....but...

When i bought my '00 gtp last year (from an older fellow) , my car was pushing out very, very little boost. it was putting out about 2 bars on the dic (i know that it is not accurate for reading boost) but it didnt feel like the car was any quicker than my GT, so i changed my bbv and no difference. i've never heard of this happening to anyone else but the black lever that goes into the blower (the bbv controls it to open or close as rpm's increase) was actually stiff and the vacuum operated bbv couldn't move it far...turns out i sprayed some rust check around the seal of this lever and it started moving free. took the car out for another spin, put my foot in it and well.....BOOST (u could feel it), and the dic read full.

The moral of this story is my lever into the blower was seizing up ...oiled it and all was well....if that engine u just dropped in sat for awhile then maybe u have the same problem.
 
^^ This. Below is the picture of the runner. Spray some pb blaster on it and work it up and down. Real simple fix if thats all it is.

runner.jpg
 


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