I'm having a problem with my new RX-7. Its a 91 N/A. I really don't know much about engines, including the rotary engine, except for the basic combustion process. It idles really low once its been on for awhile and the air conditioner also bogs it down and shuts it off unless i'm on the gas. Do any of you know what it is? Thanks lots.

 

You are going to have to study up on the differences between piston bangers and rotaries.
- Make sure your TPS is correctly set
- Then set your idle speed according to spec
- If the problem still exists, check the function of your BAC. Its purpose is to even out the idle speed when loads are put on the engine like turning on the air conditioner. The BAC valve can be cleaned and checked.

You need to call up the factory service manual and lok in the Fuel section. FSM's can be found in the FAC section of this forum.

 

could you plz tell me what the TPS and BAC is? Sorry to be such a hassle, I'm a noob.

 

AAS = Auto Adjusting suspension
ACV = Air Control Valve
AFM = Air Flow Meter (also see MAF)
A-spec = North American Spec
ATF = Automatic transmission fluid
Auto = Automatic transmission
AWS = Accelerated Warm-Up System
BAC = Bypass Air Control
CAS = Crank Angle Sensor
CPU = Central Processing Unit (the Body computer)
DEI = Dynamic Effect Intake (found on 84 and later 13B engines)
DMM = Digital Multi-Meter (required for most electrical testing on cars)
DTSS = Dynamic tracking suspension system (found on all 2nd gen RX-7s)
ECU = Emissions Control Unit (also called Engine Control unit)
EFI = Electronic Fuel Injection
EGI = Electronic Gasoline Injection
EMS = Engine Management System (aftermarket engine computer)
FB = 1st gen RX-7 81-85 production
FC = 2nd gen RX-7 86-92 production
FC3C = 2nd gen RX-7 convertible
FC3S = 2nd gen RX-7 Coupe
FCD = Fuel Cut defender (aftermarket- used only on Turbos with modifed exhaust and stock ECU)
FD = 3rd gen RX-7
FI = Fuel Injection
FMIC = Front Mount Intercooler
GS = Sporty Model (in CAN)
GT = Sporty Model with Turbo
GT Limited = fully loaded every option turbo model.
GTU = Sporty model in 88, base model in 89-90 (in USA)
GTUs = Sporty model in 89-90 (in USA)
GX = Luxury Coupe model (in CAN)
GXL = Top line Luxury non turbo model
J-Spec = Japanese/NZ/AUS spec model
LSD = Limited Slip Differential (sometimes incorrectly called Posi or Positraction which is GM's in-house brand name for their Limited Slip Differential)
MAF = Mass Air Flow sensor
MOP = Metering Oil Pump. Oil Metering Pump as called in the service manual. (also see OMP)
NA = 1st gen Miata
NA = Normally aspirated/ Non turbo
N/A = Normally aspirated/ Non turbo
NB = 2nd gen Miata
OE = Original Equipment
OEM = Original Equipment Manufacture
OMP = Oil Metering pump
PD = Pulsation Dampener
PS = Power steering
PW = Power windows
SA = 1st gen RX-7 79-80 production
Savanna = The name the 1st and 2nd gen RX-7 was sold under in Japan.
SE = Base model in the USA in 87.5-88
Series 1 / S1 = 1979-1980 RX-7 models
Series 2 / S2 = 1981-1983 RX-7 models
Series 3 / S3 = 1984-1985 RX-7 models
Series 4 / S4 = 1986-1988 RX-7 models
Series 5 / S5 = 1989-1992 RX-7 models
Series 6 / S6 = 1992-1995 RX-7 models
Sport = 86-87 Sporty model (in USA also see GS)
TB = Throttle Body
TBM = Throttle body modification
TID = Turbo Intake Duct
TMIC = Top Mount InterCooler (factory style)
TPS = Throttle position sensor
TII = Turbo model
T2 = Turbo model
VDI = Variable Dynamic Intake
WOT = Wide Open Throttle
6PI = 6 Port Induction the auxiliary ports, or the not so correct term - 5th/6th ports
13B = Normally aspirated/ Non turbo, 2 rotor, rotary engine.
13BT = Turbo charged, 2 rotor, rotary engine
13B-RE = J-spec Cosmo twin turbo, 2 rotor, rotary engine.
13B-REW = FD twin turbo, 2 rotor, rotary engine.
20B = J-spec Cosmo three rotor, rotary engine.

 

just like any other car, you need to download the service manual and follow the troubleshooting steps.

www.teamfc3s.org/main/factory_service_manual/

Just like any other car from the early 90s, idle can be affected by a vacuum leak, throttle position sensor not set right, sticky throttle body, idle support system issues (cold idle, fast idle, accelerated warmup/emissions idle), bad spark (tuneup), low engine compression, etc..

 

Is it at all possible that if they are just broken or really old that someone here may be able to sell me the parts I need? It would help greatly if that were the possibility. Thanks again.

 

You can purchase new parts from Mazda dealers, Mazdatrix.com, and a half-dozen other vendors (see the Vendor section of this forum). Used parts, which may be no better than what you already have, can be picked up on eBay or from a couple of used parts vendors that you can link to from the Vendor section or from header advertising.

First, as the nearly-6K-post man said, you need to run through the troubleshooting procedures in the Factory Service Manual which you can link to and download in the FAQ thread at the top of this section. Unless you know what to replace, it makes no sense to replace anything. Unfortunately, there is no simple, quick solution to your problem and it will require your spending a bunch of time getting smart about this car and applying your smarts to discovering the cause of your problem. Or you can pay a good rotary tech (if you can find one) big bucks to do it for you. But the "fun" is in figuring out the problem(s) yourself and in doing the repair work yourself.

If you just want daily transportation and have no interest in investing considerable time and energy in keeping a 15-year-old rotary-engined car running, you got the wrong car. Maybe you should trade it for a Honda civic.