Dat's ypipe and Stock headers

[Dawgz]

your dedication (time-wise and financially) is admirable. glad you finally got everything banged out!

what i want to know is what did you do for each of the sensors? are you running an O2 simulator? does the ecu "realize" you dont have precats anymore and throw a code, thinking it is polluting too much?

Good question!, the thing is, as u can see from the pics i posted, the sensors (which are A/F sensors) for the front and Rear header are located well before the actual Precat. So that should not, and does not throw a CEL. What i had to do though was to buy a o2 Simulator for the o2 sensors that is after the Cat, it was from URD, its called a TYPE B or "B" o2 simulator....its diffrent from the one needed for a non-pre cat System.

[Dawgz]

So, i got a CEL today after taking the car around 4000 rpm....


so i took the car to Pepboys and had them scan for codes, it pulled up P1071 i think, which is System Running Lean (bank 1)


My Dyno appointment is tomorrow, am i getting this code because the tune i had done on the SAFCII is no longer relevant or efficient because of the new and better exhaust flow?

[Midias]

My Dyno appointment is tomorrow, am i getting this code because the tune i had done on the SAFCII is no longer relevant or efficient because of the new and better exhaust flow?

I would say both your SAFC is no longer correct most likely as a result of your exhaust. I am probably being over cautious but I would try not to drive it much before the next appointment.

[Dawgz]

I called the Dyno shop and they said that could be a possible cause, that the SAFCII Tune done before with the old exhaust system is no longer relavent....


o yea, and p1071 is a typo, its actually p0171 (System Too Lean, Bank 1)




anyway, anyone else have any conclusions or ideas?

[Midias]

Oh yea when you bring it to the shop leave the code in and be nice to it don't drive it hard.

[Dawgz]

Oh yea when you bring it to the shop leave the code in and be nice to it don't drive it hard.

well, i had the pepboys guy clear the code...

but im pretty sure itll come back tomorrow on the way to the Dyno shop (its about 90 miles away)


and yea, im not gonna push the car over 3k, maybe even under.


I called toyota to see what they had to say, and the tech there said that most likely the MAF is dirty....and to use Brake Cleaner, spray it in there on the wire if its dirty, then let it air dry for 10-15 mins.

Im gonna try that IF the Tuneing doesnt fix the problem.

[Midias]

NO! NO! NO! NO! NO! NO! NO! NOT brake cleaner get crc MAF cleaner some brake cleaners will hurt the plastic.

Get this stuff from pepboys or autozone.

http://www.crcindustries.com/auto/conte ... =05110&S=N

[bassthrive]

I called toyota to see what they had to say, and the tech there said that most likely the MAF is dirty....and to use Brake Cleaner, spray it in there on the wire if its dirty, then let it air dry for 10-15 mins.

Im gonna try that IF the Tuneing doesnt fix the problem.

Don't use brake cleaner. I had a rough idle and the same exact lean code so I cleaned my MAF with this...

[Midias]

You may want to consider doing it before the dyno so you don't change anything after the dyno gets the AF ration correct.

[agent007]

use an eletrical cleaner on and clean the throttle if you havent yet...i had the same code forever and thats why i did all the replacements i listed on your other post about the a/f sensors...after i cleaned the throttle the code went away...

[Dawgz]

The thing is, this never even happend before the Exhaust work, and all of a sudden the code comes up? So im really unsure that its the MAF...eh

[sydemoid]

Wassup dawgs?

first, Nice jb on cleaning up the Y pipe... Im impressed.
As for your codes, the guys are right, your old setup was for a stock exhaust, which was more restrictive, now, the Maf error, could be associated to the engine running more open, due to less restriction.

Meaning you now suck in a lil bit more air.... use the CRC stuff, clean it, then take it to the dyno. My car isnt boosted, but this seems like the most reasonable thing to do.

-Dio

[Ian]

Not to scare you, but using the MAF cleaner can be risky. I did that when there was oil collecting in my MAF. I ended up breaking the sensor wires. I was delicate with it too.

The worst part of the story was that the oil was collecting in the MAF causing it to throw a code because my engine was blown. That's what I got for adding the cold air intake set up without adding more fuel.

Moral of the story: immediately increase the fuel flow by proper tuning as you add air flow increasing parts. A/F ratio is key.

[CamryOnBronze]

^ a cold air intake was responsible for blowing your engine because you didnt add more ful, but the ECU can compensate for a supercharger without tuning and wont run too lean? Or are you saying there were other factors...

Dawgz- Congrats on the headers bro. I would clean the throttle body and the MAF like everyone is suggesting... dont rely on the dyno to clean things that need to be cleaned. If it is a cheap task that should be done as maintenance anyway, dont skimp on it or it wont even matter if you tune the car.

Good luck with everything man.

[Eye8Pussies]

do what everybody else is saying and clean the MAF sensor first, using electrical/sensor a cleaner as shown...

if that doesn't work, then there are other possiblities as well...

first...vacuum leaks will make you throw the same code, as the ecu then can't adjust for the extra air being sucked into the engine. check for leaks using throttle-body/carb cleaner.


the other option is the most possible one though...

you had your car tuned for 2.5psi of boost along with clogged/restrictive cats

you are now running 6.5 psi on a properly running setup...your fuel needs have increased ALOT since your last tune.

normally, the ecu can adjust for the difference itself...but since you have a piggyback restricting the ability of the ecu itself....I'm not surprised that the front bank (the most vulnerable bank on the 1mz) is running lean.


your best bet right now (and from the very beginning- I should have mentioned this to you before) would actually be to bypass the safc/disconnect it from the ecu until you have a chance to retune properly for your setup