I have an 88 firebird gta. I don't think it has been messed around with too much but I have noticed a few hoses that go nowhere. Would anyone have some ideas of what they are/where they go. Here are some pictures.

Thanks in advance for the help.



Image 1: At the moment the hose goes nowhere. I also am wondering what the plug in the bottom right is.

Image 2: I suspect that one of these connects to the hose in Image 1 as they seem to have a break on the end rather than a clean cut. As for the other one I don't know.

Image 3: I think one/both of these are supposed to go to the throttle body (as indicated in the manual) but I don't know which valve it would be or why there are two of these hoses. One is the purge vac line but I'm uncertain what the other is.

 

Those are the vac lines for the cruise control and the HVAC system. Which probably explains why you only have air blowing out the defroster no matter where you set the control to.

Looks like that engine compartment would benefit from a trip to the quarter (dollar? debit card?) car wash.

 

Ahh I see, thank you. As for the purge valve, where do those hoses (Image 3) connect?

And yes a good cleaning is definitely on the list.

 

I believe that the purge vac hose goes to the throttle body to release the gas fumes to be burned. As for the control vac, it needs to have a vacuum controlled by the ecm but I cant find where there is a valve for it that goes to the ecm. Can I just tee it with, for example the pcv hose that goes to the intake manifold? In fact, do I even need both of those hoses. Why cant I just have a constant vacuum to the throttle body?

 

Mostly because the TB is the thing that CREATES the vacuum. Vacuum doesn't get supplied to it; vacuum COMES FROM IT. Vacuum is generated by the engine trying to suck the air out of the plenum from behind the throttles, butt the throttles are sufficiently closed such that less air comes back in than the engine sucks out, leaving less pressure than atmospheric (aka vacuum) behind the throttles.

The canister purge has a couple of lines from the engine that go to it. A small one that controls it, and a large one that lets the engine draw in air through the canister to dry out whatever fuel vapors it has caught. Not sure in your specific car where each of those goes. Butt given that basic principle it shouldn't be too hard to figure out.

 

Incidentally, the Schrader valve you have circled in the 1st photo, is the fuel pressure test port. Looks like the PO took the cap off for whyever (not gonna implicate s/he/it in actually testing the fuel pressure let alone ACCUSE them, butt w/e, maybe they just thought it was uuuuuggggly or something). Put a cap on it. An AC one would work fine. A tire one, although it would fit and keep the dirt out, might not be adequate. Should be metal and have an O-ring, since a fuel leeeeeeeek at that point can KILL PEOPLE. Not least, yourself.

 

Thanks a lot sofakingdom (haha just got it).
I'm planning to tee the vac control line to the hvac vacuum line (for a variable vacuum), and then put the purge vac to the throttle body (for a constant vacuum). Is there any reason I shouldn't tee it to the hvac (for some reason I don't have any empty vac valves in the intake manifold so I would have to tee it somewhere)? Also if I were to put both the control and the purge vac into the throttle body, leaving the purge control always open, would this be bad? Why cant the intake always be sucking in air from the purge canister?

 

*shrug*

Iunno... why don't we all just hack up parts of the car we don't understand rather than finding out how they're supposed to be?

How about, just put them back like they belong? aka "do it right"?

https://www.thirdgen.org/forums/tech...iagrams-i.html Look for 88 TPI in any kind of Firebird (GTA is just some stickers and cupholders out there is space somewhere, as far as engine assembly is concerned)