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Autotechnica
07-31-2003, 06:53 PM
I did this on my '92 318 before but I forget how it's done. Does anyone have the website or know how this is done? I need to make sure my "check engine" light is indicating that my O2 sensor is faulty and not something else. Thanks!

Bryan

djcontra
07-31-2003, 09:20 PM
turn the key just enough until some dash lights appear, but not all the way, and not until the engine starts.
press the gas pedal 5 times all the way to the floor moderately quick, but somewhat slowly and smoothly.
wait a few moments and the codes should start flashing
it took a few tries for me to get the gas pedal thing to work right.

bmwm5lover
07-31-2003, 10:45 PM
http://www.bonnevillemotorwerks.com/fault.html

Autotechnica
07-31-2003, 10:51 PM
Originally posted by djcontra
turn the key just enough until some dash lights appear, but not all the way, and not until the engine starts.
press the gas pedal 5 times all the way to the floor moderately quick, but somewhat slowly and smoothly.
wait a few moments and the codes should start flashing
it took a few tries for me to get the gas pedal thing to work right.

Thanks, I tried this one a few times, couldn't get it to work. I'll try it again. Are there any other methods for different DME's?

Bry

WASABI
08-01-2003, 01:33 PM
There's some interesting links at unofficialbmw.com about O2 sensors, even how to test them and clean them. They also have a link for the "pedal test", which I believe is for all OBDI e36s.

Autotechnica
08-01-2003, 02:55 PM
Originally posted by WASABI
There's some interesting links at unofficialbmw.com about O2 sensors, even how to test them and clean them. They also have a link for the "pedal test", which I believe is for all OBDI e36s.

Thanks, I actually read about the O2 sensors and how to test them at that site a while ago. I got lost somewhere towards the middle of the page.

Going to the track day? :)

Bry

Autotechnica
08-03-2003, 03:12 AM
Ok so I did the test, you have to hit the pedal 5 times REAL quick otherwise it doesn't work. Thanks to Terry for providing the Motronic fault codes.

Anyways, the results were as follows...

"1263" which refers to a "Purge Valve". Now the only question is... WHAT THE HELL IS THAT? :confused:


Thanks :)

Bry

bmwm5lover
08-03-2003, 03:20 AM
I believe it returns unused gasoline back to the tank.
It is also been blamed as the culprit for a "tick tick" noise coming from the engine. Anyone can confirm this?

Autotechnica
08-03-2003, 03:23 AM
Originally posted by bmwm5lover
I believe it returns unused gasoline back to the tank.
It is also been blamed as the culprit for a "tick tick" noise coming from the engine. Anyone can confirm this?

Interesting. However, because of this problem my engine idle is rough at times, the car doesn't start sometimes, my fuel mixture is VERY rich, and I experience loss of power and sometimes even some crazy backfire when downshifting (could be normal). And all these problems came up only after the "CHECK ENGINE" light came on.

Bry

bmwm5lover
08-03-2003, 04:00 AM
Here is something i dug up.
"Most evaporation control systems reduce the emission of fuel vapour during the time the vehicle is idling in traffic, or parked in strong sunshine by absorbing the vapour fumes into the carbon canister.
Once the engine is at its normal operating temperature the stored hydrocarbons are released into the inlet manifold where they become part of the combustible Air/Fuel mixture.

The control for allowing the hydrocarbons to be released into the inlet manifold through a cut off valve, can be achieved electrically or by vacuum: the operating principal is the same for both, our example is from the electronic solenoid type.
The electronic solenoid is controlled by the Electronic Control Module (ECM) by switching the earth path to ground under specified conditions. The purge valve/carbon canister has a 12 volt supply and its switching can be seen in the example waveform. "

Autotechnica
08-03-2003, 04:42 AM
Originally posted by bmwm5lover
Here is something i dug up.
"Most evaporation control systems reduce the emission of fuel vapour during the time the vehicle is idling in traffic, or parked in strong sunshine by absorbing the vapour fumes into the carbon canister.
Once the engine is at its normal operating temperature the stored hydrocarbons are released into the inlet manifold where they become part of the combustible Air/Fuel mixture.

The control for allowing the hydrocarbons to be released into the inlet manifold through a cut off valve, can be achieved electrically or by vacuum: the operating principal is the same for both, our example is from the electronic solenoid type.
The electronic solenoid is controlled by the Electronic Control Module (ECM) by switching the earth path to ground under specified conditions. The purge valve/carbon canister has a 12 volt supply and its switching can be seen in the example waveform. "

I also read that the O2 sensor only works when the engine reaches normal temperature. It seems that the 2 are related to each other. Still, I need more evidence that it's the O2 sensor. It's a pretty expensive fix.

Thanks for the info Terry.

Bry

Autotechnica
08-20-2003, 11:19 PM
Just an update. The engine fault code read that it was the "Purge Valve" and it turns out that the purge valve plug was simply corroded and one of the wires broke for the same reason. Once in a while I would advise spraying something on all your electrical components for longer life.

Thanks to Charlie for the quick fix. My car's much faster and more responsive now. Not to mention gas milage is way batter!

Bryan