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I was looking at my cat the other day, and i noticed that there is a sensor in the cat,i think its a secondary 02sensor.Anyway its been weld to the cat so if it is a 02 then im guess that it would be stuffed after the heat of being welded.Where can i get new 1 and whats it there 4.

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The EGT sensor illuminates a warning light which looks like a side view of the catalytic converter with wavey heat lines coming off the top of it (looks more like a BBQ!) It will illuminate when the temperature has reached around 850 degree celcius. This is very hot, and is usually due to either driving the car very hard continuously (ie: around a race track) or if driving normally is due to an extremely lean engine conditions (not good! perhaps a lazy fuel pump?)

This doesn't affect the operations of the ECU, but serves its purpose to help protect both the turbo from excessive heat (ceramic turbines in particular) from high temp failure and also to help the Platinum Rhodium material in the catalytic converter from being heat damaged.

Heat damage reduces the cat's ability to convert carbon monoxide and other poisonous gases back to a safe (and legal) emissions standards. Most cats don't work too well after 80,000km's anyway, from what i've been told.

If you ignore the warning light, then i think you'd be taking a blind eye to a possible engine problem if the light come on when you were just driving around normally (ie: not doing laps on a track)

Hmm, could be a faulty EGT sensor, but i still think that it could be indicating an engine that is running a bit too lean. I hear stories from a dyno operator i know here that sees cars that come in every day that have been so called "tuned" or "dynoed" that run extremely lean in the quest to extract as much power as possible. He says that some performance shops tune the cars so aggressively to extract as much power as possible to impress their customers, when in reality it's better to tune conservatively on a street car taking into consideration different qualities of fuel from batch to batch, different ambient temps, etc, etc. Too many variables to consider, and you should be factoring in some reliability into the engine with some form of thermal control. (A bit richer from Stoichiometric)

Anyway, i'm rambling again, get it looked into! At least check your fuel pressure and A/F ratios, as a EGT warning is a rare instance on a street car, i'm told.

um mods where safc,fmic,9psi,hks filter hi flow muffler. 212hp or round there.They told me my exhaust is causing issue's.I think the fuel pump is stuffed to.Seeings im not driving it im saving heaps of cash and im getting 3inch turbo back exhaust,255lpr pump,malapasi reg,To4e,plenum modified like a gtr style.Cause i think the turbo is a bit tired.Ill see how that runs if it still unpowerd then wolf3d,injectors,manual.I do alot of my mods myself (still building 327hp sohc vtec civic,time for body work:)

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