tbone0225

So i have beem trying to figutr out wtf is going on with my car for the last few weeks. After many hours of reasearch and BS witht he car, i think i might have found it. There is a vacuum hose MIA in my car. My first question is if the vacuum hose that is connected to your vacuum chamber behind the alternator is not connected, how much of an impact on the car would it have, running wise? Next, where the hell do i begin looking for the damn hose? i checked the vacuum diagram and i see that there is a y that the hose comes off to that goes to the chamber. Where is that y located in the car does any one know? Please help, any feedback would be great!

dankekong

iTrader: (2)

you definitely want to search for a vacuum routing diagram for your year and model rx7

but more importantly...no one can help you if they don't know what you're working on, the mods to it, etc.

dankekong

iTrader: (2)

If you can tell where it needs to go....then hook it up! go to napa or your local parts store and get some vacuum hose. Oh, and bring $5 for a t-fitting if you need one.

very cheap and easy fix....so go ahead and get cracking!

tbone0225

Well i cant see where the line y's off to before it goes to the vacuum chamber is the problem or i would have already put a new hose on it. My car is basically stock. Im trying to find out where the y is located so i can find it and fix the problem. I found the diagram. Thats how i know it y's off before the chamber

Sgtblue

iTrader: (16)

If this is the triangular black chamber behind the alternator, it's not for vacuum it's for pressure. One line goes to the Y pipe and the other to the rat's nest. One line has a check valve...the one to the Y pipe IIRC but the diagram will show it. I don't recall any t-fitting.

tbone0225

The vacuum diagram that i have for the car i got from another thread on here and it is called the vacuum chamber. At least thats what it says on diagram. Also, in the diagram it only shows one vacuum line that goes into it. I am going to try and trace it out a little better tonight after work. Thanks for the help tho!

gracer7-rx7

iTrader: (16)

Refer to this thread linked to from the 3rd gen FAQ for vac hose diagrams:
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/vacuum-diagrams-stock-simplified-sequential-non-sequential-single-turbo-749702/

Sometimes they are mislabeled.

The one alongside the alternator and behind the PS pump only has one hose. It mounts to a nipple at the front of the rats nest - 2nd from the front. Hard to see but its there.

tbone0225

OK, let me ask the noob, very noob question here cuz i am pretty new to all this stuff still, the rats nest is right infront of and under the intake manifold right? If not, where exactly is it at because i am having a little trouble finding it.

Sgtblue

iTrader: (16)

Yes, the "rat's nest" is located under the Upper Intake Manifold (UIM) and behind the pressure chamber (not pictured). It's labeled #1 below. The vacuum chamber is located behind the power steering bracket and under the alternator and is labeled #2 below.

tbone0225

Sweet, Gracer7 and srgtblue, you are my hero's. You gave me the exact info i needed. I'm about to head outside to take a look to try and figure this out. Would that vacuum line cause the problems i mentioned? Just trying to figure out if this will fix my problems.

tbone0225

The vacuum hose that was suppose to go to my vacuum chamber was hooked up to this. This was in the driverside corner uner the hood loose not bolted down or anything. hooked the vacuum line back to my vacuum chamber and the car runs great. Sounds better, boosts better and a hell of a lot more power. Thanks everyone for your inputs and help fixing this. Special thanks to gracer7 and sgtblue!



Uploaded with ImageShack.us

gracer7-rx7

iTrader: (16)

LOL. That sounds like an odd place for it.

tbone0225

Right? I always wondered what it was for but never knew enough to try and **** with it... LOL. now i know what it was for, to be a PIMA. Now just got to test the pesky check valve and hopefully get the turbos spooling properly :/

GREG5656

My 79 RX7's Tac pointer would bounce up to 1000 rpm's to 1500 plus and down again in less than a second time interval. The problem was not my wiring, it was the Distributor "Points Plate" that was lifting upwards by a 1/4 inch. Remove the 2 screws holding the plate down, and lube the bearing under it, and the weights also. (My bearing were bad, I did not feel a smooth rotation of the plate after lubeing it)...This lifting of the plate, caused the trailing points rub block to touch the cam prematurly, making the points open too soon. Test this by lifting the plate with your fingers at one end and watch to see if your points open and close. . .This opening made my RPM gauge to be unreadable, and Yes my timing was not the best and it really was the timing issue that led me to shim the plate which gave me a steady timing dwell and consequently a Tac that now reads steady. I shimmed the "Point Plate" with a thicker washer at the hold down screw, to hold it downwards preventing the 1/4 inch upward lifting, but, remember the plate must have a gap under it for the vacuum advances of the Leading & Trailing to move freely. Greg5656