RaceReadyRX7

After the the motor warms up and I drive it about 7 or eight miles. The motor starts to surge and slow (spit and sputter), while tring to hold a steady speed. If I give it more gas it smooths out. Then after a few miles of this, the check engine light comes on and it run fine. After I turn it off and back on, no light and it runs poorly (like before) until light comes on again.
The first thing I did was replace the O2 senor, with a Bosch 1 wire. I motor still runs the same. I then check for air leak in the intake...none. Nothing in the Manual applies to my problem. Anyone have any ideas?

Thanks for your help in advance, Steve.

Street King

Damn it, I'am at work and have my decoder paper at home. If someone doesn't get you the code, I will when I get home.

RaceReadyRX7

Opps. I should have included that it's a Feed Back Sencor Code. That's why I replace the O2 sencor first.

Rated R1

Mazda RX-7 codes (from Haynes Computer Codes Manual #10205) are as follows:

1 Ignition coil (trailing side)
2 Crank position NE sensor
3 Crank position G sensor
5 Knock sensor
8 Airflow meter (AFM)
9 Water thermosensor
10 Intake air thermosensor (AFM)
11 Intake air thermosensor (engine)
12 Throttle sensor - full range
13 Pressure sensor - intake manifold
14 Atmospheric pressure sensor (built in ECU)
15 oxygen sensor
17 Feedback system for O2 sensor
18 Throttle sensor - narrow range
20 Metering oil pump position sensor
23 Fuel thermosensor
25 Solenoid valve - pressure regulator control
26 metering oil pump stepper motor
27 Metering oil pump
28 Solenoid valve - EGR
29 Solenoid valve - EGR vent
30 Solenoid valve - split air bypass
31 solenoid valve - relief 1
32 Solenoid valve - switching
33 Solenoid valve - port air bypass
34 Solenoid valve -idle speed control (BAC)
37 Metering oil pump
38 Solenoid valve - accelerated warmup system and air supply valve
39 Solenoid valve - relief 2
40 Solenoid valve - purge control (auxilary port valve)
41 Solenoid valve - variable dynamic effect intake (VDI)
42 Solenoid valve - turbo precontrol
43 Solenoid valve - wastegate control
44 Solenoid valve - turbo control
45 Solenoid valve - charge control
46 Solenoid valve - charge relief control
50 Solenoid valve - double throttle control
51 Fuel pump relay
54 Air pump relay
65 Air conditioning signal
71 Injector - front secondary
73 Injector - rear secondary
76 Slip lockup signal
77 Torque reduced signal

Street King

My bad, maybe the wires weren't splice together properly, did you get the Bousch universal O2 sensor, or the Mazda RX7 O2 sensor?

RX7Elmo

yes the 17 code means the 02 sensor is bad. I think it might depend what kind of bosche unit you bought? I replaced mine with a 3 wire sensor (heated) from an escort (86) $40 which seems to be more accurate. You just need to hook it up to a 12V and teh ground for it to work etc. The factory 02 sensor is something liek $200.
Danny

PraxRX7

I had the same problem in my 1989 Turbo II...all I did was unbolt one of the exhaust bolts, wrap some 10 gauge wire in there, tighten the bolt and then run the 10 gauge to either the negative terminal on the battery or to the frame.

That fixed the feedback system problem instantly. (should work good with the 3rd gen too).

I ran a wire from the exhaust to the frame and then one from the frame to the neg. battery terminal.


Grounding is the key
(when you did your exhaust did you re-run the existing exhaust ground from factory? otherwise this will bugger up the 02 sensors early as well).

RaceReadyRX7

It's a universal. Just 1 wire that splices onto the OME wire. I know it's spliced correctly. I have a lot of experience spliceing wires. But i'll double check it, when I get home.