LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Where does this go?!

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Old Jul 15, 2016 | 03:34 PM
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Default Where does this go?!

Guys, trying to find what I believe is a vacuum leak. Bought the car last season and am still figuring out what has all been done to it. Ran across this today and wondered if it is supposed to be like this? This is the pass ever side of the intake. The previous owner did !EVAP !EGR !AIR and TB bypass. He also installed and aeromotive FPR and 30# injectors.

So, is this normal?


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Old Jul 15, 2016 | 03:49 PM
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looks like PO deleted EVAP and left the other for HVAC open...which would be a big vac leak. Either plug it or route to the HVAC so that will work
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Old Jul 15, 2016 | 10:07 PM
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Are you referring to the upper hose or the spot underneath it? The one on the bottom is plugged with a metal plug. The top one just has the weird hose and valve on it. Where would this normally terminate?

I did find this tube in the harness at the back passenger side that looks as if it could fit/reach the tube in the first pic...do they go together???


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Old Jul 16, 2016 | 02:01 AM
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Originally Posted by germ79
Are you referring to the upper hose or the spot underneath it? The one on the bottom is plugged with a metal plug. The top one just has the weird hose and valve on it. Where would this normally terminate?

I did find this tube in the harness at the back passenger side that looks as if it could fit/reach the tube in the first pic...do they go together???


They should go together. After that, the HVAC should blow in more than just the defrost position.
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Old Jul 16, 2016 | 07:27 AM
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Just an observation, I think the PO misunderstood what injectors he or she had. Looks like you have the Ford SVO "yellow tops" which are a 19# injector at 43.5 pressure (stock LT1 pressure). IIRC, that's less injector than stock. Worth noting, the PO may have altered the pressure with that fancy FPR.
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Old Jul 16, 2016 | 10:41 AM
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Originally Posted by germ79
Are you referring to the upper hose or the spot underneath it? The one on the bottom is plugged with a metal plug. The top one just has the weird hose and valve on it. Where would this normally terminate?

I did find this tube in the harness at the back passenger side that looks as if it could fit/reach the tube in the first pic...do they go together???



Courtesy of Shoebox

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

it does not matter which vac port the HVAC and FPR go to, either top or bottom one. The PO plugged one and left the other open...which will be a vac leak

i would make sure the FPR has a vac hose connected and the HVAC also so that stuff works

Originally Posted by StealthFormula
Just an observation, I think the PO misunderstood what injectors he or she had. Looks like you have the Ford SVO "yellow tops" which are a 19# injector at 43.5 pressure (stock LT1 pressure). IIRC, that's less injector than stock. Worth noting, the PO may have altered the pressure with that fancy FPR.
IDK if those are Ford or Accell injectors...stock are 24 lb
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Old Jul 16, 2016 | 10:57 AM
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First off, you guys are the best. I appreciate the time you've taken to help me out. I've been hunting for this leak for awhile - hoping this is what is causing some weird fuel trim issues on my passenger side.

Ok, the injectors are Bosch 0280150785 - seen here:


I think those are indeed 30#'ers.

The Aeromotive FPR can be seen in the lower left of this pic, with all the braided hoses running to it.


The vacuum line from that is running to the top nipple of the intake in the driver's side shown here:


Does that seem right?

SO excited to maybe have something finally figured out here!
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Old Jul 16, 2016 | 12:35 PM
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IDK where the upper vac line is going towards the front of the motor....it would normally go t the EGR (rear of motor) but you deleted EGR..

http://shbox.com/1/egr1.jpg

The one on PS going nowhere is a hard vac leak that way unless that "round thing" is some kind of check/stop valve essentially sealing that line
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Old Jul 16, 2016 | 12:47 PM
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Originally Posted by ******
IDK where the upper vac line is going towards the front of the motor....it would normally go t the EGR (rear of motor) but you deleted EGR..

http://shbox.com/1/egr1.jpg

The one on PS going nowhere is a hard vac leak that way unless that "round thing" is some kind of check/stop valve essentially sealing that line
That upper line is the vac line for the aftermarket FPR. Is that ok?
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Old Jul 16, 2016 | 01:20 PM
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Originally Posted by germ79
That upper line is the vac line for the aftermarket FPR. Is that ok?
yes, any vac port off the manifold will work

if you can find the HVAC line around the firewall area in the wiring harness (IIRC it is a hard plastic line) run that open one on PS to it or cap it off.
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Old Jul 16, 2016 | 06:02 PM
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Ok. It definitely was pulling a vacuum, so I reconnected it and voilá, the car "seems" to be running more smoothly and my vents now work in the car!

I need to hook up the computer and see if this resolves some of my split BLM issues - I'm sure hoping so!
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Old Jul 17, 2016 | 08:02 AM
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Originally Posted by germ79
First off, you guys are the best. I appreciate the time you've taken to help me out. I've been hunting for this leak for awhile - hoping this is what is causing some weird fuel trim issues on my passenger side.

Ok, the injectors are Bosch 0280150785 - seen here:


I think those are indeed 30#'ers
Okay awesome. I was a bit concerned for you at first because they look exactly like the SVO yellow tops (19#'s) which are also made by Bosch.
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Old Jul 17, 2016 | 08:04 AM
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Originally Posted by StealthFormula
Okay awesome. I was a bit concerned for you at first because they look exactly like the SVO yellow tops (19#'s) which are also made by Bosch.
I appreciate it! I need all the lookin' out that I can get!
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