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Vacuum line hack job, explain to me why or if they were on to something

Rammey2009

New member
I just picked up a 1997 gtp with 1/4 million miles for cheap. It needed a s/c coupler, but upon further investigation it needed alot more. It needed the LIM changed and upon taking the snout of the s/c there was no oil in it and the bearings were toast...that was the easy part. Now looking at it and looking at a diagram, there are alot of vacuum related parts that were deleted, I'm posting two pictures, one of what I have and another of what i can assume it should look like....Were they on to something with deleting so much or on something...
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2011-07-04_145638_vacuum.jpg2011-07-04_145638_vacuum new.jpg
 


prolly they were going off a 98+ diagram, the 97 had a different vacum setup, i believe it was an extra tree
 
They added/deleted more than just a tree...the whole evap system is gone...and why a vacuum line to the washer tank?
 
Well ...first off no vacuum goes to the washer tank. Close though. The washer tank has it's own line and the line you think goes to it, actually heads to the vacuum can that is buried in the drivers front fender.

It looks like the evap was removed from your diagram. As well your boost control is missing and therefore running off vacuum which it can do w/o problems. Look at your vin. What is is the 8th digit?
 
Does the supercharger have the tree on it by the boost actuator? Likely it doesn't. Only 96/97 production motors (GP only saw the motor in 97) had the tree by the actuator. They they changed it up for some reason and ran things in a less complicated way.
 
lol what? i see that now lol hillbilliy ingunity. well they delted the evap as some ppl do but why run anything to the washer line? Do your hvac settings work? like will it change from bi level defrost?
 


bill you do realize i had to replace all my vacum lines in my 97 to get my HVAC to work right? ive been through a 97 vacum system before. maybe i didnt retain all the info but im just a shadtree mechanic, leave me alone lol
 
I'm not just seeing things, they had a vacuum line from the TOP of the washer tank running to the top of the s/c...on that 3 way vacuum port....Crazy ....shouldn't that run into the firewall(?) instead?....8th is "1"...I guess if it can run without the evap system..that's great but the s/c boost control..that's my concern
 


Ok,

1. They eliminated the boost control from the sound of things and it's running off vacuum. This is ok, or you can hook a soleniod back up.
2. I was asking fo the vin, to determine if it was a top swapped or a real GTP. It is a real GTP
3. Triple check that washer line. The route of the vacuum line to the can is right along with the washer line and unless they were trying to drown the motor with methanol (most washer fluids) then it can't go to the charger. A test is to try the washers on the car. If they work, it's going to the canister and not the washer tank.
 
Ok, Theres a line from the top of the s/c going to the boost control, and on the other end where it is supposed to go to the solenoid it isn't capped off...should it be? There is a washer line running to the wipers from the pump..I've never seen a vaucuum line run like this...Where should it go otherwise? somewhere with the hvac? or capped it not needed?
 
Also there is no codes thrown. seemed to had run fine except for a noisy s/c...boost gauge seemed to work on the dash..Only got it to go about half, but didnt really get on it either..
 
No arguement from me that it's goofy. It runs along the front bumper and over to the vacuum ball.

IMG_5815.jpg


IMG_5816.jpg


Somewhere the vacuum is either t'd and goes into the cabin or it comes off the ball and into the cabin on the driverside. I didn't trace it all, but enough to see it's goofball.
 
Well, i'm stumped...I didnt even have a vacuum ball in the fender...wtf.....Well if the boost contol can run off vacuum..great we'll leave it be...until I get the car running and see what's really going on, this was a huge help!
 


Some may not have the vacuum ball. But then that really confuses me as to where they routed the line and why they went around the car w/o heading to the ball or going into the cabin.
 
All in All that one really doesnt concern me yet...It was the evap deletion and the boost controler that i was worried about
 
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