O2 Hack

[daewooluvr]

I remember reading about someone using an inline transistor to fool the ECU into thinking the O2 sensor was returning a good code.

My front pre-cat blocked up and was hollowed and I really don't feel like shelling out over $300 to replace it and don't really need it.

Does anyone have any information on how to trick the ECU into thinking the O2 sensor is reading correctly?

[woo99SE]

IDK how you get to the conclusion that you don't need a O2 sensor, unless you have a carburator, chipped ecu or a stand alone ecu, if you are using a tuned ecu the software used can deactivate the O2 and no cel light.
now if you are using a regular ecu with few mods, be warned that the O2 is what tells the computer how the engine is running when hot, if you use a resistor that by luck sends a signal = to a rich mixture and the ecu decides to compensate and lean it out, be ready to melt a spark plug, crack piston rings.....

jmo

[benzino]

So your problem is that you deleted the front cat and now your 1st or 2nd o2 sensor is throwing a code due to inefficiency...

try installing an o2 sensor spacer on the sensor that's causing the issue

[daewooluvr]

So your problem is that you deleted the front cat and now your 1st or 2nd o2 sensor is throwing a code due to inefficiency...

try installing an o2 sensor spacer on the sensor that's causing the issue

I've already done this and it still throws the code.

I ended up buying a new cat for $180 grr

[daewoomofo]

i know this is late but there is a mod chip that you can use to fool the ecu into thinking that you have a second o2. basically the ecu only needs the first o2 to determine the needed fuel trim adjustments. the second o2 is to be used to ensure that the first cat is doing its job. i have a very good friend that has a civic that was baught with out a second cat. since it was either spend a bunch of money for a cat or make one of those 02 foolers for about $20 he choose to make the 02 fooler, works good, no cel. basically it just has to send a varying voltage to the ecu

more info
http://www.supraforums.com/forum/showth ... sor-Fooler

[daewoomofo]

Correction, friends car has no first cat, chip was used to fool ecu on second cat

[daewooluvr]

Thanks, I ended up putting on a new 1st cat to correct the issue.

[Puddle31]

is that a cat a muffler shop keeps on hand? How much is a new cat? those aren't cheap. they are worth a few bucks just for scrap. a few years ago people were cutting them off cars and stealing them to sell.