Exhaust tempature problem

[DaveTheWhiteAsian]

So my car is spitting back the code P0546 and it fails emissions.

I took it to the dealership for them to run diagnostics and they said my car has a straight up pipe with no pre cat and its not getting hot enough. so obviously there recommending i buy the factory uppipe.

Anyone else have any other ideas on why this is happening or if this sounds correct?

[SilverTurboRidin]

i think they sell things to make the computer think that the cat is still there

[TROLL]

do you have the stock EGT probe back in the uppipe? what did you do with it? you might need to wire a resistor in place if you havent already. if you have, check it ot make sure its still good. i've got a feeling your issues is there.
its definitely not with a catless uppipe being installed in place of the stock one.
bryan

[thewake]

do you have the stock EGT probe back in the uppipe? what did you do with it? you might need to wire a resistor in place if you havent already. if you have, check it ot make sure its still good. i've got a feeling your issues is there.
its definitely not with a catless uppipe being installed in place of the stock one.
bryan

It is the fact that there is no cat in the uppipe, or it has failed.

Follow this:

No cat or failed cat in uppipe -> EGT sensor does not read proper value (or is removed) -> ECU sets code (P0546 - Exhaust gas temperature sensor circuit high input)-> Fail inspection

There are two things you can do. First (legal) is put a cat back in the uppipe. I realize that this may cause many sleepless nights as you worry that your car is no longer 'Teh Fastarest' in the universe. I have news, there is always somebody faster. Second (not legal for highway use, emissions tampering) you can remove the EGT probe and plug the hole, then add an electronic device of the proper resistance in the connector from the ECU. It will then appear to the ECU that the EGT probe is reading in spec.

[DaveTheWhiteAsian]

well i bought the car in the condition its in. Now i dont have the cash for a new uppipe so the catless one will have to stay. The dealership told me that the sensor is "there and working correctly but giving low readings" they actually changed their mind on it before they told me that it was too hot, now its not hot enough so honestly i dont really trust their opinion not that i ever did in the first place. I'm really wondering if this is a normal problem when you install a catless uppipe and the correct way to fix this without really doing any rigged jobs.

[TROLL]

here's what i say:
get the appropriate sized bolt and plug the hole up where the EGT sensor goes, then get the right resistor from radio shack for under a dollar and use that instead of the probe. leave the probe in a box somewhere in your garage.
done and done.

[DaveTheWhiteAsian]

Theres one other problem with that when i took my car to get inspected it threw back a couple of codes 3 cylinders misfiring, obviously randomly or else i wouldnt be able to get down the street and another one about fuel mixture or something. This was also when my utec was in it was on 0 so im assuming it was running on the stock map. But I took it out the day i went to the dealership and they didnt encounter cylinder misfire or the fuel sensor so im assuming those 2 problems were from the utec. But if it wasnt i dont wanna cause more trouble then I already have

[TROLL]

ok at this point i'm going to have to ask you everything that is done to your car... if you dont give us all the info than we're not going to be able to help

[DaveTheWhiteAsian]

From what i know it was just a utec which i took out and the up pipe but i know it had a lot more **** i talked to you about it on the phone that one night a bunch of wires are cut going into my ecu so i need to get the wiring schematic for that but besides that thats it. The car took a lot of abuse i know that as a fact

[TROLL]

hmm, glad nobody else ever had their hands in my engine bay...

i dont know what the misfires are all about... is the utec running a base map? if you dont know much about the utec i wouldnt use it unless you take it to get tuned. have you gotten any CELs since you took the utec out?

bryan

[DaveTheWhiteAsian]

I took the utec out and since then they said they havent gotten cylinder misfire or the fuel sensor so im assuming that it was from the utec but i have no idea im keeping it around for now until i get more parts and then ill get it tuned. Yeah i wish i had the money to get one no one has touched but that I couldnt do it so i have to deal with what ive got.

[TROLL]

if you got a CEL you'd know because there'd be a "Check Engine" Light on your dashboard, hahah. so if there isnt, then you dont have one.
yeah good idea on not using the utec for now. at least have someone who is familliar with them look at it and how its set up, could have some totally different map loaded onto it.
bryan

[DaveTheWhiteAsian]

Yeah, the check engine light is on right now but that should be because my tach broke unless one of those cut wires is keeping the ECU from reading some kind of error

[TROLL]

autozone will pull codes for free, or find a friend with an accessport to pull your codes.
also look into the cut wires on your ecu asap... they have got to be messing with something

[JoeScooby]

cut wires on the ecu is never a good thing. If you tell me the plug number (connecter label) and terminal number (Start from first wire as #1 top left on the connecter *DISCONNECTED LOOKING AT IT*) I can let you know what exactly they are controlling/system it belongs to.