I need help finding what this hose is for and how and where to reattach it to the car

Help greatly appreciated, I just got my girlfriend's FD running again and there seems to be exhaust coming from the engine bay and I hope this tube has something to do with it.
If it helps at all, it was found completely unattached in the upper left corner of the engine bay.
Her car is an automatic 1993 RX7.

Thanks, TW

 

Looks like an omp line, if the car is sequential I feel sorry for you, you have to strip the top of the engine down to the block to replace it. It wont cause the exhaust smell but will cause oil to leak on top of the engine.

 

Is that something I can reasonably be expected to be able to do myself without obliterating the car?
I'm much more familiar with working on my FC, so I don't wanna get in over my head if possible.

 

It requires the removal of hte UIM, Rats nest, primary fuel rail and a decent bit of other things. It all depends on how stock the car is, removing the rast nest on a sequential fd is no small challenge within itself. All depends on how familiar you are or want to become with the stock sequential system

 

Is that 1/2 of the water tube to the over flow tank ? Most omp lines that I have bought were clear, I have made a set or two from SS braded line,they were silver .

 

looks like it goes to the AST.....part of the cooling system. I'll almost bet thats it...the bend on top is where it would attach to the AST nipple. The ast is attached to the stock IC if you still have that.

 

and the OMP lines are def clear but that have a black protective shielding over them....that is definitely not a OMP line.


I got my money on the AST coolant line or thats just a random vacuum line...maybe to one of the BOVs or from a previous boost gauge.

 

I could be wrong but that is awefully small for a coolant hose. The only coolant line in the said area is the rear iron to TB coolant hose and it is much larger than that.

 

By the way it's twisted I thought it might have been the OMP line too, and it seems just the right size, but I also agree with Garco, it's not clear or silver, but you never know. DJSeven has more than likely disassembled more FDs than I have.

Can you take a picture of where you found it? Maybe we could take a better guess that way.

 

Looks like just a vacuum hose. You can't actually buy a hose like that. You need to buy a length and cut it to size. The hose is shaped that way from repeated heat cycling. Look up the vacuum diagram and see what you are missing. Most people replace those hoses with silicone.

 

It was laying drooped across the top of the rats' nest.
Just totally disconnected, and sitting there randomly.

 

its kind of hard to tell size by the pic...maybe throw a penny in there for comparison.

But yea....I think that because it's your gf's FD and she probably doesn't know too much about it that it is just a vacuum line that is in the bay from a previous owner. Take a picture of the UIM...there are two nipples that are usually used for an aftermarket BOV or boost gauge.

It doesn't have anything to do with with your exhaust leak and I think it has been laying around in the bay for quite awhile.

You said you got her car running....what was wrong? Does the car perform ok...as in it boosts and accelerates like an FD should?

 

also...there are vacuum lines for the OMP injectors...make sure those are still intact....

in any case...if the hose in question came off you should have a vacuum/boost leak somewhere....how's your idle?

 

It might help if you provide a little background to "I just got my girlfriend's FD running again". What was done to the car?

 

The car had been sitting for a bit because it wouldn't start, it would just crank and not turn over.
I used the deflooding procedure and that didn't seem to help.
I also replaced the battery because it was cranking weakly at one point.

I went out today and tried to turn it over and it started to catch, something it hadn't done for awhile. So I kept trying and it finally turned over, and after a minute or two
I noticed maybe birthday candle amount of smoke coming up from the intake and turbo hoses area and it smelled like exhaust so I shut it down.
Both turbos sounded like they were spooling and the idle was normal while it was running. There was no check engine light and I checked the coolant level before running the car.

We had noticed the mystery hose awhile back and like I said it was just sitting on the rats nest.
I had hoped the hose would be the cause of the smoke due to leaking coolant or exhaust from a uncapped point rather than something horrible like a stuck turbo or exhaust leak.

 

Did the car drive fine before all the sitting...like boost fine?

The smoke could possibly be from a leak and the car is blowing some extra smoke because it's been sitting for a while. Let it warm up and then look around where it is smoking. Look carefully and definitely shut down if it's leaking oil or coolant onto the manifold.

 

Yep, it boosted normally before the sitting.
When the car started up, it did the normal puff, could the smoke be from the puff recirculating through the turbos?
I only ran it for a minute till we noticed the smoke.

I'll check tomorrow if there's any fresh oil or coolant on the manifold or surrounding area.

 

Is the "windshield washer" hose that runs from the hood to the bay still there? Looks like this pic.

 

Yep. To me it looks like either the washer line or a line from the evaporative purge system. There aren't too many vacuum lines that long in the vacuum system (maybe one of the lines to the pressure chamber).

 

The washer hose line to the hood is connected and this is not that hose.

 

Take a look at the vacuum diagram, compare it to your GF's engine see if you have something missing:

http://fd3s.net/vacuum_hose_replacement.html

We can play "guess that hose" all day long, but at some point you are going to have take a look around the engine since we can't.

 

update: the car starts fine now with no smoke from the engine bay.
The smoke must have been from a dead leaf on hot metal or something stupid like that.
After running the car for about 15 minutes and shutting down, coolant started spilling out around the coolant reservoir area so I either have a split coolant reservoir again or the mystery hose problem is solved.
My main question now is about something odd that happened while I was running the car.
I started it up and it was running at about 11-1200 rpm, probably from the accelerated warm up procedure or whatever it's called. Throughout the time that I was running the car, as it came up to running temperature, the RPM gradually started to drop. Near the time at the end when I turned off the ignition, the RPM was at about 200 and the car was wanting to stall out.
Can anyone give me any input on what they think the problem might be there?
It has enough fuel and I just recently checked the plugs, so I'm puzzled.

Thanks, -TW