Backfire

Well I had the stock exhaust on the car. It backfired a lot. I never had this problem with any car and I never new anyone with this problem. So just to be safe I bought a new Exhaust system and did the usual tune-up (plug, wires, oil, filters). Well I still have the backfire and its really annoying. Does anyone know if this is a bad thing and if there's anyway to fix it?

uhm, it's a rotary? Don't like it go back to pistons.

thats not juss because its a rotary there captain.... my 7 never backfired till i took the exhaust off and was runnin strait from the down pipe.... but.. u got a cat on it? and what kinda exhaust..stock? ( the new one) and does the engine sound alright???

Ohh I know, but if it's an NA it usually backfires more then a turbo:P At least that has been my experience.

well the 13b-rew's dont come NA they are all TT. And the new exhaust was an Apex N1 exhaust. The engine runs great. Only 70k miles. Been taken care of buy an old lady before I bought it. Have records of tune ups and shtuff every 3 months or so.

backfire is caused by unburnt fuel in the exhaust

so maybe your fuel mixture is too rich.

backfire is normal on rotaries, but if its excessive, check the engine codes the ecu throws and come back

You know how much Mazda wants to check the codes on my buddies car? 2 hours worth of shop time for a 3 minute job.

might be a good idea to go ahead and get the codes ran like drftkid said... or get a A/F gauge (air fuel ratio)

might be a good idea to go ahead and get the codes ran like drftkid said... or get a A/F gauge (air fuel ratio)


A/F guage is practicaly useless withotu a wideband O2.

you can get a lean rich guage, but there junk too :P

im pretty sure you can check the codes yourself

Yup you can check the err codes yourself.

86-88: http://fc3spro.com/TECH/HOWTO/ERRORCODES/ZENKI/zerror.html
89-91:http://www.1300cc.com/howto/how2/codes.html
93-96:Jump the TEN and GND pins inside the little black Diagnostics box. The box is under the hood on the drivers side, it says Diagnostics right on it. Once you do that turn the key on and watch the Check Engine light, it'll blink out the codes. Here's a list with instructions that I took from a website:

ECU Error Codes

To cause the ECU to flash the error codes on the MIL, short the TEN and GND terminals on your diagnosis connector, with the ignition off. Then turn your key to the "on" position and count the flashes.

To clear the error codes, disconnect the negative battery cable for at least 20 seconds, and depress the brake pedal. Re-connect the battery cable.

In the "pattern" column, the "L" stands for a long flash, and the "S" stands for a short flash.

Code Pattern Problem Memorized
02 SS Crank angle sensor no NE signal Yes

03 SSS Crank angle sensor no G signal Yes

05 SSSSS Knock sensor open or short circuit Yes

06 SSSSSS Speedometer sensor Yes

09 SSSSSSSSS Water Thermosensor open or short circuit Yes

11 L S Intake Air Thermosensoropen or short circuit Yes

12 L SS Full Range Throttle sensor open or short circuit Yes

13 L SSS Pressure Sensor open or short circuit Yes

14 L SSSS Atmospheric pressure sensor (in ECU)open or short circuit Yes

15 L SSSSS Oxygen Sensor less than .55v for more than 120 sec in feedback mode Yes

16 L SSSSSS EGR Switch open or short circuit Yes

17 L SSSSSSS Feedback System No change for 25 sec in feedback mode Yes

18 L SSSSSSSS Narrow Range Throttle Sensor open or short circuit Yes

20 LL Metering Oil Pump Position Sensor open or short circuit Yes

23 LL SSS Fuel Thermosensor open or short circuit Yes

25 LL SSSSS Pressure Regulator Control Solenoid open or short circuit No

26 LL SSSSSS Metering Oil Pump Stepping Motor
open or short circuit No

27 LL SSSSSSS Metering Oil Pump Sensor open or short circuit or MOP sticking Yes

28 LL SSSSSSSS EGR Solenoid open or short circuit No

30 LLL Split Air Bypass Solenoid open or short circuit No

31 LLL S Releif 1 Solenoid open or short circuit No

32 LLL SS Switching Solenoid open or short circuit No

33 LLL SSS Port Air Bypass Solenoid open or short circuit No

34 LLL SSSS Idle Speed Control Solenoid open or short circuit No

37 LLL SSSSSSS Metering Oil Pump low battery voltage Yes

38 LLL SSSSSSSS Accelerated Warmup System Solenoid open or short circuit No

39 LLL SSSSSSSSS Releif 2 Solenoid open or short circuit No

40 LLLL Purge control Solenoid open or short circuit No

42 LLLL SS Turbo Precontrol Solenoid open or short circuit No

43 LLLL SSS Wastegate control Solenoid open or short circuit No

44 LLLL SSSS Turbo control Solenoid open or short circuit No

45 LLLL SSSSS Charge control Solenoid open or short circuit No

46 LLLL SSSSSS Charge Releif Solenoid open or short circuit No

50 LLLLL Double Throttle control Solenoid open or short circuit No

51 LLLLL S Fuel Pump Relay open or short circuit No

54 LLLLL SSSS Air Pump Relay open or short circuit No

71 LLLLLLL S Front Secondary Injector open circuit No

73 LLLLLLL SSS Rear Secondary Injector open circuit No

76 LLLLLLL SSSSSS Auto Tranny Lockup Signal open or short circuit No

77 LLLLLLL SSSSSSS Auto Tranny Reduce Torque Signal
open or short circuit No



If more than one failure is present, the codes will be indicated in numerical order, lowest number first.

Well its def not that the fuel is rich. I have to use crummy 90 Octane here on base. Thats the only affordable gas i can get. Unless I wunna go offbase and pay about $160 to fill my tank. Of base is the nice gas 95 and 97 Octane.

maybe you dont understand what "rich" means;

its when the engine gets TOO MUCH fuel at a specific time, it has nothing to do with octane rating

maybe you dont understand what "rich" means;

its when the engine gets TOO MUCH fuel at a specific time, it has nothing to do with octane ratinggotcha...idk. I guess ill check those codes. Thanks guys