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What is this? It's on the passenger side of the intake manifold. It has an electrical lead to it but nothing attached. There is also a port (assume vacuum under this unit for a total of three attach points. The other pic looks like a vacuum line coming up the left side fender (black with a wide white stripe)
What year?
Looks like a distributor vac advance relay.
port at rear goes to the advance pot on the distributor.
port at the front goes to vac
port sticking out toward fender is a vent that should have a filter over it.
part of your emission system.
It's part of the TCS system, would have been inline between the carb and the vac-advance on the distributor. Basically it kept the vac-advance off at idle until the engine warmed up.
That Vac-line....I'm trying to think but I remember the lines going through that area as the larger PCV line, the main line to the vacuum tank and the smaller on that goes out of the firewall to control the headlights (looks like that's in your picture). But that makes the line shown appear to be the main vac-line for the tank...
Where does the other end go to?
M
Hi,
Here's a picture showing the TCS solenoid with the electrical connection, the hose from the distributor's vacuum advance and the hose running from the solenoid to the carb port.
The small white striped hose is likely the line that runs from the vapor canister to the carburetor. It's hard to tell though from just seeing one end of it which appears to have been cut short. You can see that hose in this picture too.
Regards,
Alan
The red line shows where I now have a vacuum line coming from the distributor to the carb. I just realized that it is spliced, so it appears that the line should go where the two blues lines are. I realize that your line is going to the side of the carb and mine to the front. I don't think my carb is stock. The leaves one port open that Hammerhead Fred states should have a filter.
As far as the other bigger black line with the white stripe, I can't see where the other end goes,..but it seems to be near the vapor canister. Someone has just put a screw in the end of it. All systems work (flip up lights, wipers, etc) so not sure about this
.
Red line is current vacuum from dist to carb. Blue line is correct?
Last edited by mtnance; Dec 22, 2014 at 09:25 AM.
Reason: order of statement
Alan's right (no surprise there) there is a line that goes to the vap-can along with the pvc hose (forgot about that one, damn those aluminum pans)
Before you hook up that TCS solenoid, make sure the rest of the system is working, depending on the transmission it's tied to there also
M
I was fiddling with the pictures for the post when yours popped up. So now this might make sense,...the black line with white stripe might should go where my "now" line from the distributor is. (See my photo above for where the "red line" now goes.
I just looked at the carb and the line that Alan has in his pic is "capped" on my carb. So, that where I should have a line just as he has in the photo. line from the dis advance to the TCS, then from TCS to carb,...to where mine is now capped. Then hammerhead fred stated the one remaining open port of the TCS valve should have a filter. Does this sound like it makes sense?
Not sure why someone has rerun these lines,...if only that the TCS valve is bad. I'll need to hook these up and see what happens. I just didn't want to be cruising down the road and all of a sudden, die.
Buried in this thread is some / most of the info on the TCS wiring that applies to the 72 (71 had it's own CEC thing which is different than the rest for whatever reason)
Keep in mind that the auto / manual were slightly different and the 350 / 454 were slightly different
The TCS systems were frequently disconnected on the way home from the dealership Really all they kind of did was make the motor run hotter at idle to try to burn off more hydrocarbons (or whatever they wre back then) by retarding the timing, once the car was hot or into high gear it would override the system and act normal.
If you look at post 8 in that link, Monte has a good diagram of the system for a SB-standard, post 11 has the info for the automatic.
Hook it up if you want it to be original, but it's of no benefit otherwise.
M
What year?
Looks like a distributor vac advance relay.
port at rear goes to the advance pot on the distributor.
port at the front goes to vac
port sticking out toward fender is a vent that should have a filter over it.
part of your emission system.
A search will get you all the details.
So now we have better photos I correct the above with the
port sticking out toward the fender goes to the distributor
and the
port toward the rear of the car is the vent requiring a filter - you can put some filter foam over it if need be.
So that black w/white stripe either comes directly off the vac reservoir OR it comes from the vapor recovery tank ( not trusting that the PO has it running to the original location).
Likely the later in which case it should route to the front of carb to recover tank fumes. If it comes off the vac reservoir then it would go to the larger of the two ports on the check valve (which I can't make out in your photo) before going to the check valve filter then into the intake.
Okay, perhaps this will be better. I read that this part is only on the 72. The photo shows:
Yellow line is what is current, vacuum line going from dist to carb (but there is a inline splice at the yellow hash mark). I personally don't like anything spliced.
The red arrow shows the capped end of the larger black vacuum line with the white stripe.
The yellow arrow shows a capped port on the carb.
The blue circle is a line that some may have been referring to as coming from the canister to carb. It has a "T" connection and is attached to the emission valve on the left valve cover.
And obviously, the purple arrow shows what started this, the Transmission Spark Control with nothing hooked to it.
I will say the the current line going to the carb (yellow line) seems very loosely fit on the carb. Hardly any effort at all to pull it loose.
Except for this topic (and the valve covers/air cleaner) not much else has been touched.
And, I guess I need to say,...I am not trying to be original just don't want to create an issue This car has the 4-speed.
Last edited by mtnance; Dec 22, 2014 at 11:42 AM.
Reason: added a line
For the Vacuum line with the white stripe:
There are several lines that come across the top of the brake booster box.
One Larger one that goes from the evap-can up and T's to the PCV valve in the valve cover, and continues on to the fitting at the front of the carb.
One goes down and into the firewall through the grommet with 3 holes in it. This one comes from the vac-tank under the fender
One that comes from the back of the carb (intake actually on mine) that goes through the valve/filter and splits into two, the smaller one going into the firewall through that grommet again and the slightly larger one goes over to the vac-tank
The last one basically follows the PCV one up from the evap-can to the front of the carb
but doesn't have anything to do with the pcv valve
M
(ignore all NCRS sins, dirt, general FUPs in general)
Yep, that looks like the same line. See arrow. Where you have that line connected, someone has inserted the vacuum advance line. So, it appears I need to swap some lines around.
Sounds like someone has just discombobulated your emissions stuff. Make sure all the pieces are still there, move your vac-advance over to another manifold source (or ported and check your timing). check to see what is off or on the evap-can and re-hose, it doesn't hurt and saves some gas smells
I'd leave the TCS out if your not worried about stock, just box it up and put in on the shelf for the next guy.
M
Hi,
The white striped hose that comes out of the 3 hole vacuum hose grommet in the firewall is the one that connects to the hose running to the vacuum storage tank.
I think the unconnected white hose in the first pic is likely the one that comes from the vapor canister and ends up at the carb…. but it does look too short, so may have been clipped.
Can't see everything in total, but that's my guess.
It's as shown in M's pics!
Regards,
Alan
I have this file photo of my 1972 L48 engine that I hope will help you with TCS routing.
It's a quirky old system, but I find it kinda fun in that it's so basic now but so advanced at the time. Its design is as described above (retarding timing). Since my car is NCRS, I do keep it connected and have not found it to cause the engine to run hot, even in peak summer stop/go traffic.
I hope this is of some help to you...
Last edited by redrdstr72; Dec 23, 2014 at 08:07 AM.
Yes, this photo helps a lot. I can see that the hose (cut short on my car) connects to the carb. and the TSC solenoid with the vacuum hose. Fortunately, not much else has been chopped on my engine bay. Thanks again.
Part ID please
Really all they kind of did was make the motor run hotter at idle to try to burn off more hydrocarbons (or whatever they wre back then) by retarding the timing, once the car was hot or into high gear it would override the system and act normal.
