[lvnurs9]

http://www.clubsciontc.com/modules.php?nam...ic&t=1997#16973

 

[whosthatrussian]

eh.....same 2.5" pipe....what's really the point in the full cat back exhaust if the piping is already non restrictive? There are also no numbers that show gain over the stock set up. I'm not really impressed.

 

[zoltiz]

I would probably consider a midpipe if they sold it separately (kinda like stock one, except without a second cat).


This thing:

 

[jito72]

I be with you, zoltiz, too!
I woul like also the downpipe along with a good header like the 4-1 DC Sports. Thats means no cats anywhere, no "check engine" light on, no rumble noise since we keep the OE factory muffler which is a "high performance" once a time it opens the high flow valve.

 

[lo bux racer]

You'll need an O2 sim for no CEL. No way around that.

 

[jito72]

Nope, No O2 sim is need. I already checked.

 

[zoltiz]

Originally posted by jito72@Jan 3 2005, 10:43 PM
Nope, No O2 sim is need. I already checked.

If you will have a DC header / no cat between the first and second O2 sensor you will need an O2 sim, or will end up with a cel. And it's not a "maybe" it's a given.

 

[hanskloss]

Originally posted by jito72@Jan 3 2005, 07:43 PM
Nope, No O2 sim is need. I already checked.

how did you check this out? I ordered the DC header and now I am wondering about that O2 sensor and a check engine light, let me know, thanks

 

[basilisk4]

This has been reported repeatedly on other boards by people who have bought the DC Header.

 

[TRDsparks2]

Originally posted by basilisk4@Jan 5 2005, 04:24 AM
This has been reported repeatedly on other boards by people who have bought the DC Header.

I might be wrong, but wasn't there a post about DC withdrawing the headers for a while because of that problem?

Ken

 

[zoltiz]

I talked to DC guys and they said that since it's a race header they are not planning to do anything about this problem.

 

[FrostbytetC]

That makes sense zoltiz. If its for race (off road) use only, it would not have to be street legal meaning you can have no cats, no o2 sensors.

 

[drmechanize]

ok guys the tc runs on a obdII system you need the 2 o2sensors or it will kick on the engine light and set a dtc for the o2 sensor on obdII first o2 adjust fuel and second monitors emissions but the work together by taking one out of the exhaust or taking the cat out will set a code so i suggest if you gonna mod the exhaust system try to mod it with the cat and keep the 2 o2sensors in the system

 

[lo bux racer]

header=no cats.

Might not be an OBDII issue, it could also be reversion. Toyco uses VVTi to create EGR without a conventional EGR system. It's very possible the EGR function is upset and setting a code. It is also possible the ECM is having to correct A/F excessively and it is causing a code to be set. Without scanning one with the header it is impossible to know what is going on.

 

[drmechanize]

late 95 is when OBDII was started and still is today unless you telling me toyota/scion invented OBDIII and i didn't get the update on my genisey scan tool by OBDII you have to have two o2sensors once your in closed loop both is monitor by the pcm if one is missing then a dtc will set if only running one o2 you might damage your cat, poor fuel (too rich too lean) not worth the head ache

 

[lo bux racer]

No you don't. You need to have a signal going to the ECM that makes it think there is an O2 sensor in two places. There are O2 simulators that many have used on cat-less setups to simulate the second O2 sensor's signal and make the ECM think the cat(s) is/are OK.

The first O2 handles A/F ratio, the second one is just to ensure the cat is doing its job. While it would be foolish, maybe even stupid to remove the first O2, many owners running without cats have installed O2 sims to fool the ECM so the engine CEL will not illuminate. Do a Google search for O2 simulator, you'll see a number of them available from different sources.

 

[suprakilla852611]

lo bux pulls through again.....

 

[Check_Raise]

sorry im a newb, but the first cat is connected with the header right? where is the second cat located then? does the dc sports header come with an o2 simulator? because from the picture ive seen for DC header, there is a little hole for an o2 sensor to go. same place is in the stock header the tC has right now.