SouthernScion

My check engine light remains on with the dc sports header i purchased. I was wondering if keeping the light on hurts hp/tq. Ive reset the ecu several times and whenever the light does kick back on, i think i feel a slight difference. It may be my imagination. Im too lazy to go get the ani foulers and such. Comments suggestions???

toyota_scion_tc

Yes it will hurt your power. Your car will be running in limp mode with the cel on which means it forces your cars engine to run rich loosing hp. It might actually cause your car not too advance the timing completely to gain all the hp you would have without the cel on.

ScionBandit

it does, yes.
had mine dyno'd before light was on and after light came on, a slight difference
but you can def. feel it run a lil poopy after the light has been on for a bit

XD40tC

Does it affect it a lot though? Cause a friend of mine has the DC header and doesnt have the antifouler OR his main 02 sensor hooked up and he ran 165whp with header, intake, axleback injen, and crank pulley. That seems pretty good...

SouthernScion

that sucks!!! So can i buy the anti foulers at the nearest auto parts store? I have the usual I/H/E

SouthernScion

I mean, with my set up, what could i do to get the most out of the header. I figured the CEL would make the computer compensate in some way. Do the ani foulers even help?

ScionBandit

i dyno'd 168whp with I/H/E before the ligth came on
dyno'd after and lost a slight amount of power, but light was only ran on for 2k
i rec. to get it taken care of and to not leave it on, it will only harm the engine, not help

SouthernScion

Really, so im actually looking at 160-170hp with the I/H/E? So hows the cel taken care of?

ScionBandit

around that, yes

cant give you anything exact until you dyno your own car

BuddhasTC

the hp difference shouldn't matter. If you throw a CEL, fix it. If you don't, many worse things can happen to ur car than a loss of a little hp IMO.

Prototype_xB

The Anti-Fouler tricks the secondary O2 into reading roughly the same O2 voltage that it would if there were a cat. Tricks the car into thinking it has a cat. Limp mode dosen't drop that much hp on the tC because the ECU has a strick fuel maping that it follows and uses a Narrowband primary O2 that makes only very fine tuning to the fuel gain/cut.






Very very generic readings. Other motors like Honda b-series and k-series or anything for that matter that uses a Wideband primary O2 have graiver loses in limp mode because a wideband can read very very detailed levels of a/f (some up to 12 samples a second). Typical Wideband voltage analysis:








Hope i could help

SouthernScion

Any loss of HP still sucks. Thanks for the imput guys. And the graphs, prototype. That explains alot!!! I figure us NA tc's need all the power we can get to really get the benefit the 2.4 has to offer. But, as mentioned there could be worse things than a thrown CEL.

ScionBandit

this is tru, you will be running rich, which will cause loss in HP and down the road
more damaging issues.

so get it fixed!!!

DTRUONG_112

on us turbo'd guys, when the cel comes on, it causes a rich state casuing a good amount of power loss. Joe from dezod had a case where he was on the dyno and the CEL came causing about a 40whp loss if I rember correctly.

ScionBandit

it will hurt you FI guys more than N/A guys

bronxblaza117

i would get it fixed cuz wat if somethin was really wrong with ur car... you would think it would be cuz of the o2 sensor but can be somethin worse!! id fix it fast

SouthernScion

Will do. So i should get the antifoulers? (sorry if i keep askin this over) I really dont want to take the headers off!!

ScionBandit

start with anti-fouler
www.racingsolution.com

dgHotLava

when you throw a CEL and the car goes into 'protect or limp mode' it will stop adjusting the VVT stuff. thus you are not getting the most of the motor. that is your loss of power.
it will also run rich (lean will blow the motor). if you run rich for too long you could hurt the Cat conv.

SouthernScion

ok. About how much do those antifoulers cost? Does the local auto parts store carry them? One last question. Is it a sunday job or less?? Thanks again guys and gals!!