WyomingTII

I don't know what it is. I own two rx7's and this is stumps me. My 87 TII has had idle problems ever since I restored it last year. Now a new problem's popped up. It'll idle just fine until I give it a little gas (or more) and get some boost. Then after I boost it acts like it has a vacuum leak. The idle goes up, leans out and sometimes surges from 1500-2000 rpms. I've dealt with a lot of vacuum/boost leaks but I've never had one that pops up only after I've used the turbo. Just an FYI, it's got the stock ecu with a fuel cut defender from racing beat and a few other mods (intercooler sprayer, cone filter, aftermarket exhaust etc)

barkz

iTrader: (1)

Does it stop or do you have to shut it down and restart it?

WyomingTII

I have to shut it down and restart it, then it idles fine until I boost again. Also it goes away sometimes when I apply the brakes.

SirCygnus

iTrader: (1)

vac leak.

WyomingTII

But where would it be? And why does it only show up after boosting?

barkz

iTrader: (1)

Anywhere that there is a vacuum line.... start the car, spray starting fluid around vacuum lines, wait for idle change.

WyomingTII

Okay then I have one last unanswered question. Why does the idle change only after boost?

barkz

iTrader: (1)

Because boost is the opposite of vacuum.

WyomingTII

Alright, well I found the vacuum leak. It was on the seal around where the wires enter the fuel pressure regulator. Now just to replace it. Thanks for the info. Is there anything else I need to replace while I'm down there?

barkz

iTrader: (1)

If you've got wires going into your FPR I think you've got bigger issues...

WyomingTII

well it's a big metal cylinder on the back of the motor. It's coming out from under the UIM and it has two wires going into the side of it. What is it then?

satch

iTrader: (1)

And the wire colors are?

HRnico

iTrader: (7)

Aux air valve?

satch

iTrader: (1)

Or maybe the BAC.

WyomingTII

One black and white wire and I can't remember the other one. It's not the bac valve, its brass colored.

lastphaseofthis

iTrader: (8)

Pic?

Got me curious

WyomingTII

yeah, I will upload them tonight. I don't know if it's supposed to be there. The car sat for 9 years and the people who had it before me did a lot of stuff to it

WyomingTII

Here they are

WyomingTII

sorry for the bad quality. The wires are black/white and blue/white

clokker

iTrader: (2)

EGR valve.

WyomingTII

Are you sure? I thought the egr valve looked more like a dash-pot. This is more cylindrical.

barkz

iTrader: (1)

So you ask what it is, thinking it's something it's not even close to being, then when someone tells you exactly what it is you question it?

No no you're right, that's you FPR...

sir revalot

Injector seals.....

I had exactly the same symptom on a 7M-GTE Supra..

sir revalot

clokker

iTrader: (2)

My S5 has no EGR so no, I'm not sure.
All I did was look at the wiring diagram and find the wire colors you described and it said "EGR".