92 Mazda Protege - Check Engine Light - Help Requested

We have a 1992 Mazda Protege DX with 136,000 miles on it.

For the past week or two, when the engine reaches operating temperature the CHECK ENGINE light goes on briefly, then goes out again. The engine runs normally, except for the occasional rough idle - which is not a new problem these past few weeks.

We contacted the local dealer and they informed us that they no longer carry the software to run the diagnostics on a Mazda this old.

We also contacted several local independent shops - same problem - they don't keep the old software updates.

What are our options? Should we consider purchasing a multi-meter and attempting to read the codes ourselves?

The only recent repairs we've had to make were a year ago, when the engine was overheating and that was radiator hoses, thermostat and sensor replacement. Other than that, the car runs normally, doesn't burn oil and there's been no change in the mileage we get.

Any suggestions will be appreciated. Thanks!

once 1 thing goes its like a dominoe effect. but you prolly be alright. if the light comes on briefly and there are no performance changes you should be fine. maybe have your water pump checked.

i had to walk a whole 30 seconds to go to my car and get my repair manual for it, so i hope you appreciate this!!! lol, just kiddin, seriously though, i hope this helps:

connect a jumper wire between the TEN and GND terminals at the DIAGNOSTIC test connector in the engine compartment... make sure the transmission is in neutral, engine is at normal OPERATING temperature (HOT!!) and all accessories are off and so on...

after you've checked all of the above, turn the ignition switch to ON BUT DO NOT START THE CAR!!

now, if there's any problem detected the check engine light will flash a certain number of times...

most of the codes are 2 digit numbers... it'll flash the first number slowly (eg: 3= 3 flashes with long intervals between each of them...) then the second in quick succession...

if it IS a single digit number, the light will just flash quickly to signify the number... no long pauses between flashes...

now, here's what ur after...:

error codes:
02 distributor ne-signal------> check the distributor and PCM (powertrain control module) circuitry or components...

03 distributor g-signal------> same as 02

08 airflow sensor------> check the airflow sensor circuit from the sensor for an open circuit or a screwed sensor

09 coolant temp sensor------> check the coolant temp sensor for an open circuit or a bad sensor

10 intake air temp sensor------> check the intake air temp sensor for the same as 08 and 09

12 throttle position sensor------> check the TPS sensor for same as 08 09 and 10

14 barometric pressure sensor------> this sensor is integrated into the PCM check the PCM power and ground circuits... if you don't find anything, replace the PCM...

15 o2 (oxygen) sensor------> check the o2 sensor for the same as 08 09 10 and 12

17 o2 sensor has detected a rich or lean condition------> check the fuel and ignition system performance (fuel injectors, fuel pressure, intake air leaks, ignition misfires...)

25 solenoid valve (fuel pressure regulator)------> check for a broken circuit between the solenoid valve and the PCM, check for a broken circuit between the valve and the fuel injection main relay, or check for a defective valve...

26 solenoid valve (purge control)------> same as 25

34 IAC valve------> same as 25 and 26, except between the IAC valve, of course, and the PCM...

41 solenoid valve (VICS) (DOHC ONLY!!!)------> same as 25 and 26....

anyway, just so i don't get sued, all this info was taken from the haynes 1990-2000 mazda 323 and protege repair manual...

hope it helps some!!!!!!

usually a fault like that is given where either the calalist is giving a bad reading (i that car is new enough to have o2 sensors on the cat.)

what will happen is the engine will warm up but one of the o2 sensors will have a bad read. this is pretty common where people dont do tune ups on time or drive the car while it is overheating.

if your cat is bad it could also cause the o2 sensor to give a bad read, thus causing the engine light to come on and go off.

nevertheless, normally if the light does not come on at the start of the car, and does come on after warm, and or fluctuates, it is probably o2.

you could also leave it alone....had a 93 protege lx..had the check engine light start coming on at about 120K miles as well..no real pattern to it, sometimes depended on what gas i used...ended up doing nothing as the car was running fine and the fix was around 180.00 for a new sensor..the car even passed emissions at 148K...

To clear the code- disconnect the negative side on your battery, step on the brake pedal for about 10 seconds, then reconnect the negative side to the battery and start her up...it worked for me! :smokin: