FAQ: Vacuum Hoses & Lines (Series II SC)

Mr.Riviera wrote:

little late, but here is what's on my car. (pics taken literally 5 min ago, so sorry about the dirty engine
I tried to color code it as best i could. the only one you cant see where it goes is the one under the snout on the lim.

Awesome!!! So the second line on the TB splits to the tree and the tranny. What about the underside of the EVAP Vacuum Switch?

So, my plan is to connect the PURPLE line in this pic to replace the tree. Can you see any problem with doing so?

the evap vac switch line is shown in a burgundy color in pic 3.
only thing not shown is where the white line connects on the back of the MAP sensor b/c i couldnt get a pic of it.

If it were me deleting the tree, i would run a line from the vac port that isnt used (caped off from factory on 96's, next to brake booster) down to a T and have one end of the T run to the FPR, the other en going over towards the TB. split it again to have one end enter the TB and the other go down to the transmission.
that leaves the orange vac line still missing. maybe run a T from the light blue line?

Edit:if you can replace the tree with a make shift tree running from the purple line in your pic then by all mean do it. it will be cleaner than what i was suggesting. should work fine as long as the purple line/tree is large enough to support 3 run offs.

Here is a visual of the other thing I was wondering about...

BRB...

there is a fuel line running to the opposite side of the burgundy port. that is all i see on mine. i dont know for certain it has fuel in it, but it is the same type line and runs back to the pack of lines on the firewall.

Grrr!! So these Vacuum diagrams were not clear that the line from the tree to the tranny had a "T" in it to connect to the bottom port of the TB!!

From the diagram, it looks like a direct line. It would be a lot easier too if I had the stock lines with stock elbows and T's. This was set up with just a bunch of parts store vacuum line, so I haven't seen a real live picture of how the lines really run. Just trying to go off the Diagram here, which seems to assume that you are working with the stock stuff.

Well, I hope I can get this to work right. And I think I am going to trade my old S/C for a rebuilt one, so I have the real Stock S/C with all proper connections.

Another question, is there a was to buy a complete set of stock Vacuum lines, All pre-cut to the proper length, with the correct elbows, and hard lines?

And after I get my Stock one rebuilt and installed, what do you think this on would sell for either here, the Grand Prix site or eBay? If you have the right car for it, it works great, and no play in the snout either!

Mr.Riviera wrote:

BRB...

there is a fuel line running to the opposite side of the burgundy port. that is all i see on mine. i dont know for certain it has fuel in it, but it is the same type line and runs back to the pack of lines on the firewall.

I think the line you are talking about is the No.1 in my diagram pic, (To EVAP Canister [At Rear of Vehicle])

If anyone needs the login, PM me and I'll gladly share with you! It is for http://www.alldatadiy.com. I signed up through AutoZone.com.


P.S. I will be deleting the Login info in 1 hour so I can try to make sure only members are using it, and in case the company monitors how many computers are logged into my account at the same time. Then I'm out my 29 bucks I spent on this 1 year deal.

Ok, well I think I have figured out some good little info.

I was hooking up an air compressor to different vacuum line hook-ups in my old S/C on the bench. Here is what I have learned I will reference the diagram I posted to explain....

1st I blocked off 2 of the 3 ports on the top of the S/C No.4 and No.5, then blew air into the 3rd hole, when I did this the pulley on the snout started turning, but when I opened the Bypass, the S/C Pulley stopped turning. Since I am blowing air into it instead of it being a vacuum, we need to think backwards here. So, when the engine is running those 3 Vacuum ports on top of the S/C (including the one I tried to hook up to the tree) will have a various amount of vacuum pressure depending on how much Boost pressure is going into the engine, and how much is being bypassed.

Next, I hooked the air hose to 1 of the "Vacuum Tree" lines, and blocked the other two closed. When I blew air into that line, nothing else was affected when the boost bypass was opened or closed. So that should mean that the amount of vacuum pressure from the "Tree" would be a constant and unaffected by the amount of boost.

So, connecting the "Tree" to the No. 5, would not work because the things that operate off the vacuum pressure from the "Tree" need a consistent amount of vacuum pressure.

So.....now I am wondering what will happen if I use a "T" fitting off the top TB vacuum port (Not the bottom, because it already has a "T" for the tranny, if the car will run right on that configuration.

So, I'll BRB right after I try this. Wish me luck!!!

Nope that did not work either!!!!

I have to be missing something important here, 'cause I know I am not the first to replace a 96 S/C with a newer one!!

Looks like I am putting the old broken one back on until I can get a rebuilt one actually made for a 96, or I find a good one off a 96 at the junkyard. The car did run well before all of this, minus the lack of boost and the low oil pressure, so switching back will be the same except it will have good oil pressure just no boost. Oh well, I tried!!

Well, I am very very happy to be wrong. Apparently, doing the huge list of things mentioned earlier was opening a giant can of worms!!

I hooked the old broken S/C back on, luckily I have become a pro at this and can do it in about 20 min now lol, to find out what is wrong. I found 2 vacuum leaks, after replacing all of the lines with fresh rubber lines. One was from the metal tube from the intake to the EGR valve, and the other was a bad fuel injector O-ring.

So, I fixed all of that, then put caps on the lines from the tree, and used my 3-way vacuum splitter, and hooked it up to the acc. line, and the car runs great. So...first thing in the morning I am putting the working S/C back on.

And I have discovered the MASS Air sensor is broken from when my friend flipped the engine over when we were doing the crank and bearings. So, I might pick one up from the bone yard.

Hi, Im new to this forum but what I see so far I like. My question is does anyone know where I can purchase a vacuum hose kit for my 1996 Riviera. They all seem to be getting soft and need to be replaced. Thanks, Tom

just go to any parts store and buy hose by the foot. take a sample of the few different size hose under the hood,they are all concentrated on the right side facing of the engine and take into store , buy same size as samples and start spending your hard earned dosh! isnt life grand!

Thanks for the input. I noticed one of the vacuum hoses is "U" shaped and at one end it is about 3/8" and the other end is about 1/8". Do auto parts stores carry something as odd as this? Thanks, Tom

not sure which one your talking about? 3/8 to an 1/8 sounds like it might be particular to the 96? any difference u can zip tie down

it's the vac line connecting the EVAP(i think) to the throttle body.
i havent been able to fine that type fitting at any local stores. nor have i been able to find the odd T connecting the TB to the transmission on the 96's. go to the local dealer and ask for the vac kit in the vintage parts. i was able to get it about 2 years ago, not sure if they can still get it for you now though.

Mr.Riviera wrote:

it's the vac line connecting the EVAP(i think) to the throttle body.
i havent been able to fine that type fitting at any local stores. nor have i been able to find the odd T connecting the TB to the transmission on the 96's. go to the local dealer and ask for the vac kit in the vintage parts. i was able to get it about 2 years ago, not sure if they can still get it for you now though.

About a year ago i had a dealer searching for it nationally and they couldn't find the vacuum kit anywhere in the country. I now have mine rigged with custom vacuum tubing. Its not pretty but it works.

Mr.Riviera wrote:

it's the vac line connecting the EVAP(i think) to the throttle body.
i havent been able to fine that type fitting at any local stores. nor have i been able to find the odd T connecting the TB to the transmission on the 96's. go to the local dealer and ask for the vac kit in the vintage parts. i was able to get it about 2 years ago, not sure if they can still get it for you now though.

If you could possibly find the receipt with the OEM P/N on it, we can do a search and also see if Monsterpartsonline.com can find one.

ok i bought the stuff feb of 2005.

24503990 vac line
24503881 vac harness

those are the 2 part numbers on the "Vintage Parts L " receipts.
glad i keep all that stuff

i get a hit on the second part # for 12.21 at monster, but no pic to know if it's the right part or not.

OK I will try those part numbers through my dealer. Thanks everyone for all of your help , I really appreciate it. I'll keep you posted. Thanks Again, Tom

Hi Guys, I have another question. Where exactly is the evap canister located on my 1996 Riviera? Also is it easy to get to? Thanks, Tom

The canister itself is under the car, near the fuel filter. basically under the drivers side rear passenger. The evap go from the throttle body to the evap switch, on the rear of the intake manifold.

OK, I will take a look and see if it is bad. Again, Thanks for the help, Tom

In the "HELP" Section at most auto parts stores they have "L" Fittings. I bought a bunch and replaced all of my lines, it looks pretty good. Vac tubing is cheap, so I just bought 10 feet of every size they had, and saved the extra.

Well that my friend means that..you have enough tubing for all the members of rivperformance the entire life of Our vehicles! on behalf of all the members at rivperformance...thank you!!!! (ps. dont forget to inquire about our mailing info) thanks...