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P0136 Code

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1.5K views 1 reply 2 participants last post by  BAM  
#1 ·
Ok, so if any of you followed my post not too long ago about my hardships with a certain dealership, you should know I was having problems with my 02 sensors.

I searched around for other people with the P0136 code, and saw a common problem which I fit under as well.

First - Borla headers
Second - Mil Eliminator

At first when I got the code over two months or so ago, I didnt notice any problems, until maybe about two weeks ago when my car idled weird, at about 500 rpm... It would hang at 1k while coming down from revs, then drop to 500 abruptly, and it would feel like a bucking bronco. it even stalled on me a couple of times.

The apparent solution actually isnt to remove the MIL eliminator nor get spark plug anti-fouler for the rear. The problem actually lies with the Front 02 sensor. It sends the computer a bad signal, then the computer receives a signal from the rear 02 sensor and when it tries to compare the results it gets confused and accuses the rear sensor of treason, erm being faulty.


Oh and if you are still under warranty and have aftermarket exhaust, they HAVE to cover it =p. As it was explained to me by my warranty people, the exhaust has no effect on making an 02 sensor go bad. Bad gas, too high octane, etc, will cause 02 sensors to freak out.
 
#2 ·
Higher octane fuel, bad plugs, bad plug wires, contaminated fuel, bad coil pack will all foul a front O2. Also, the rear O2 sensor will never affect the performance of the car. You can completely remove the rear O2 and the car will function properly. It's main purpose is to meter cat efficiency.

A bad front O2 will most definitely affect your cars performance. If left untreated, it is quite possible that a bad front O2 will destroy your motor. It usually goes like this:

Cylinder 3 plug wire separates inside the port. Cylinder 3 misfires. Cylinder 1 plug then receives weak ignition pulse from excessive load on Cylinder 3 causing Cylinder 1 to run excessively rich and misfire. CEL is thrown. Faulty plug wire causes coilpack to fail from overload. Front O2 sensor becomes fouled causing ECU to improperly manage fuel. Conditions deteriorate and bore wash occurs. Oil becomes contaminated from excessively rich a/f mixture. Oil loses viscosity. Oil blows through the rings and then blows the lid off your $100 catch can through your non-functioning hood vent spraying oil all over your windshield and into your face.

-Brett