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Discussion Starter · #1 ·
The only CEL code that has plagued me is the ever popular P0420. Low cat effeciency code.

My car has now gone more than 300mi CEL free (knock on wood). As many of you know, this code will come on AFTER the car has been driven up to operating temp 3 times. Basically self checking to see if there really is a problem, then POP... CEL comes on. Now, NO LIGHT! :cool:

I've tried several different approaches to solve this problem. Basically here's what has worked for me.

This is a MIL eliminator. Purchased from Pony Express. In its original form, it is basically four wire ends, a cap, and a 2.2k resistor. The resistor gained me nearly 200mi CEL free. I tried a 10k ohm and the CEL comes in 50mi or so. And now a 1k ohm seems to have dones the trick. In short: MIL eliminator, replace the 2.2k resistor with a 1k.

My exhaust setup:
PDE Upipe
TurboXS 4" downpipe
TurboXS CAT pipe and midpipe
Blitz axle-back

I will post an update after many more miles. Hopefully this may help other TXS users in the same situation.

FYI> I will also be using a TXS test pipe for trips to the drag strip. I will use matts (his clubwrx username eludes me now) approach to fix the potential CEL problem with this pipe. For those who haven't seen it, this basically moves the O2 sensor out of the direct path of the exhaust gas.
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