NHrhdFD

iTrader: (1)

Ok,

I do not really post much on here, mostly buying parts and looking for advice. I am usually stubborn and try to figure things out on my own. However I am in need of some help so I am going to try and describe this as best as I can.

I bought a 97 fd from japan, had it imported and all dot approved ect ect.
I am currently having a couple issues, these might seem weird as they do to me, but this is my first rotary and I am hoping to get some input from you guys.

Bought the car and it was backfiring like crazy. I know before it got sent to me from japan it had a power fc in it (due to the sticky on the dashboard and 2 missing ecu screws.)

So I went ahead and ordered the correct power fc and had it sent from japan. After installing it, it no longer backfired and was drivable. I am currently having issues with boost, when I hit boost it starts boosting and when I hit about 5-6k rpm, the boost drops to 2lbs or so. Then if I shift it goes straight to 2lbs and no more, Unless.. I let the rpm's drop below 3k and then it has full boost again until I hit 5-6k rpm then 2lbs..

Now there is a lot of unknown factors when importing a car, I had a local rotary guy check it out and this is what we came up with.

Engine could possibly be built (Ported and half bridge) by the sound of it
It has 2 intakes, axle back exhaust, boost gauge and ARC radiator.
Engine was compression tested with a oem mazda tester and has 90+ on all face's.
It is currently running on the basemap from apexi
We did a smoke test and boost leak test, replaced all the lines as well as some of them were a little dry (expected from a 20 year old car)

If anyone has any idea what could possibly be happening, this would be a great help. Thank you for your time and I look forward to hearing back!

Thanks!
Nick

DaleClark

iTrader: (55)

Sounds like the common turbo control door problems, go through the boost troubleshooting pages. It may be a little trickier as you have the "black box" under the intake manifold and not the separate solenoids.

Could be a bad check valve in the black box as well.

Dale

EVAN616

iTrader: (2)

I'm in the process of trouble shooting mine as well. The secondary turbo just stopped coming online the other day. I have also had problems with smoke (ONLY) at start up after sitting. So I tore into it. Intake piping very oily, but Y-pipe only appears oily from primary turbocharger.

I now have UIM off and have verified all the check valves are fine, including the PCV. Although I will probably get a set from Dale (Who has been very helpful to this point).

I started looking for oil culprits... The nipple that faces down off the Y-pipe inside that goes to the LIM has oil pooled a the top of the vacuum line. The metal pipe that connects vacuum lines from the oil injector (check valves), and the two solenoids for wastegate control turbo precontrol also has oil all over it.

I then notice.

The previous owner of this car replaced one of the check valves with, what appears to be, one of Dales check valves. The one from the Y-Pipe to the Pressure chamber. It looked oily, INSIDE..... so I took it off and blew through it fine one way, not the other, good deal.

I took the pressure chamber off to realize it was almost completely full of oil.....

I did a search and came up with this thread, but its talking about the vacuum chamber.
https://www.rx7club.com/3rd-generati...ed-oil-199724/

My next step is going to be checking the solenoids one at a time. There is a problem in the turbo system somewhere...

As for the oil... I think it is the oil injectors (check valves)? The PCV is fine, although I'm going to ditch it and cap it like the 95's. It ONLY puffs smoke on startup after sitting, and stops.

I'm not trying to hijack a thread. I was going to post this separately, but I have a similar problem, and maybe we can figure them both out.

Any thoughts, questions, suggestions would be appreciated. I'm just like the OP, I'm a lurker, I hardly ever post....

Evan


EDIT: What is confirmed Working.

All black and green check valves.
PCV valve.
CRV - Brown (It starts to crack open at 4.3 in/Hg., troubleshooting says 6.5 in/Hg.) Is this a problem!?!?
ABV - Black
Actuator (Charge Control)
Vacuum chamber holds vacuum

NHrhdFD

iTrader: (1)

Thanks for all the input Evan!

EVAN616

iTrader: (2)

I ordered clear silicon vacuum line today. I'm going to find out where this oil is coming from one way or another.

Jeff5808

iTrader: (7)

Do you know if the emissions are still in place? It was probably backfiring like crazy when you got it because it was in limp in mode. Was the check engine light on? I believe the power fc instructions tell you not to install their ecu until your car is running good on the stock ecu, if the car is stock that is.

Sounds like a vacuum problem with your solenoids tho, the dreaded rats nest. There's a way to test the solenoids, you need a mighty vac and an oven, you also have to remove them. I'd replace the check valves with dales, and check all the solenoids. Since you have a power fc, I'd get a banzai block plate kit and remove all the unnecessary emissions stuff too. That way if a solenoid is bad you might could sub it for one of the ones you wouldn't be using possibly?

EVAN616

iTrader: (2)

Well I am still waiting on my vacuum line, but I have most definitely found my problem.

3rd solenoid from the front on the bottom of the rack "solenoid valve(turbo control)" has one of the vacuum nipples broken off of it. The vacuum line is so hard that it was holding it there in place so it didn't immediately stick out like a sore thumb.

Now for the oil problem.

JP's 93 fd

iTrader: (28)

I had a similar issue where my primary turbo was boosting properly (10 psi) and when it went above 4500 rpm (secondary turbo kicks in), it dropped down to 2 psi or less. The problem was when I replaced all the vacuum lines, I mistakenly switched two vacuum lines. I swapped the charge control solenoid and turbo control solenoid vacuum lines by accident. I swapped the lines back and it fixed my boosting issues.

I recommend familiarizing yourself with the system and a good start is to check the following:

-Check all your vacuum lines, solenoids, and check valves. Heres a diagram.
http://www.turborx7.com/images/Techn...e_diagram2.jpg

-Check out this website if you haven't already
Mazda RX-7 3rd Gen Stuff

Good luck!!!!