cant we just remove the vacuum line in the engine bay?
it looks fairly simple

 

Maybe the line is clogged... or something is backed-up? If the turbos are leaking oil (blowing oil into the compressor side), will the residue find it's way through the vacuum lines and into the solenoids?


I recall pouring oil out of my intercooler a year ago when I replaced the vacuum hoses, so I know my turbos are leaking.

 

Got a pic of where it's at?

 

No, but its the big actuator right next to the oil pan on the passenger side... abou the size of a coffee can. It has a line going to the front of it (vacuum), and one going to a nipple hanging off the side of it (pressure)... they go a short distance to a set of hard lines in front of the turbos that head up to the rack.

Honestly, you COULD remove the hose at the hardline, but its easier just to jack up one side of the car, slide under, and pull the hose loose at the actuator.

 

Dumb question:

If I pull it off do I need to plug any holes/hoses?

 

It's really hard to get to unless you remove the undercover.

 

if its the tca that controls it cant you just get a new one? also i have another ? i took off that little black box on top the engine ( brain fart cant think of the name right now ) and found a sky blue female eletrical hook up where does it go to cus its just sittin in the open now ( dont let people who dont know rx-7 work on rx7 they **** it up ) any know where it goes??

 

the two lines that go to the tca are also located at the top near the coolant hose.I can take a pic of it if youd like.Its basically behind the radiator filler neck and underneath the pressure chamber. same question as batmans though.Wont removing one of these lines cause a boost leak of some sort?

 

i didn't.

 

and it just fixed it?

does it feel different? anything I should expect?

 

The connector is for automatic cars I think.


edit: BTW, the little black box is the flight data recorder... j/k. It's either the pressure or vacuum chamber, I get that one and the one in front confussed.

 

that was good. nice pickup on my dumbass ( its the pressure one the vacume chamber is on the front side of the engine

 

I would think so. Otherwise, when the TCA solenoid opens, the system vacuum will be lost through that pathway. But it might not be open long enough to empty the system - not sure.

Dave

 

It's not hard to get to and you do not have to remove anything... you're thinking of the two actuators at the front of the turbos... this is by the oil pan..you can practically see it by looking under the car.

The actuator normally gets pressure applied to one side, and vacuum to the other simultaneously... it uses both for speed. When I disconnected my pressure, it worked better... but its just a little slow in both directions.. a little slow to transition up, and little slow to get back.... but something must be keeping the pressure applied when when it should be transitioning back, so affectively the vacuum is fighting with the pressure. Realeasing the one, lets the other do what it wants.

 

HDP, can u guinea pig that and let us know?

 

.

 

That is what the TCA looks like. It is located on the front side of the turbo manifold. Simply unplugging a line going into it will create a vaccum/boost leak. What I reccomend doing is to print out the vaccum diagram and start digging inside your engine bay to look for loose/disconnected/slashed vaccum hoses. Then go out and buy a MityVac and check all of the check valves and various chambers that hold vaccum or pressure. That is a good start.

Have you guys even looked though this site? http://www.autosportracetech.com/RX-7/rx7stuff.htm

It has a wealth of information that you guys might want to try out before you go out buying various parts. In my situation, it ended up being a loose hose (going into the boost side of the TCA) that appeared to be okay. I had the exact same symptoms and spent a good part of a month trying to hunt the problem. Get into that vaccum assembly and start pulling/wiggling hoses!

 

Thanks for the info. I'm sure I will refer back to it before it's all said and done, but I'm almost certain my problem is with the solenoid and not the actuator. Not unless the actuator can cause a solenoid to malfunction and that is what the PFC is reading.

 

I just replaced that solonoid with a brand new one and fresh silicone lines, and so did Dave Disney from the other thread, so don't hold your breath.

 

so its obviously not the solenoid or vacuum lines. what about the electrical connector? im thinking its an electrical problem.
my solenoids are fairly new.and i checked the vacuum lines without any luck.
with as many guys having this issue sooner or later someone will figure it out.If I do sumble onto a fix ill post up my findings.Im going to be checking the vacuum chamber and also the check valve that goes to it.

 

I was thinking the same thing. I have this problem and have check everything. I have a new TCA on and new hoses everywhere. I've had the UIM off probably 20 times testing crap. I checked the solenoids and then swapped them with others just to see if there was a difference and there hasn't been. I've done every test I have found and everything appears to be working fine yet it still doesn't work right. I even cleaned all the contacts on the solenoids to no avail. The only thing I can think of now is that I have a wiring harness or a ground problem or possibly, from Dave's thread, that the PFC is more picky about solenoids.

 

that may be.but im not running a pfc
so how do you explain the fact that some of us have these same problems and dont happen to have a pfc?
its not it.most likely a short in the harness thats probably triggered by the transition to secondary boost.

 

Well, maybe it's the actuator or the flapper door... maybe the full moon, ... high tide, ... alignment of the planets, ... after effects of left-over tuna casserole...

 

Ahh. If people have the same problem without the PFC then I am with you that that isn't the problem but having the PFC might make the problem surface quicker. But again none of us know what the problem is yet so the PFC might just be conjecture.

 

Awww, the hell with it! I think I'm just going to go full non-sequential...