**CEL after catless downpipe install, HELP ME**

[mcgti6]

and yeah, i got the test pipe file. but it didnt turn off the CEL

 

[SkullV]

No it isn't. The check engine light has NOTHING to do with the exhaust traveling at a higher rate. It monitors the oxygen content of the exhaust to see how clean it is, not the speed at which it moves.

Yep, the downstream o2 is only there to monitor CAT efficiency. Has nothing to do with exhaust speed.

 

[yoffer]

The downstream o2 sensor wont change your afr's. The reason it throws a CEL is because the exhaust gases are traveling through at a much higher rate because of the freeflowing design and the o2 sensor is unable to get a reading. The o2 "spacer" is used to bascially "sniff" the exhaust gases so the o2 sensor can read it (this is the assumption i am under) ive heard some o2 spacers still throw a CEL but ive heard great reviews from the 42dd o2 spacer working very well. Or you can get flashed stg2 if you choose, but i heard that going stg2 is just to get rid of the CEL on the dash, it doesnt actually give you more power. But if you have the option too, you might as well get the flash anyway.

Yep, the downstream o2 is only there to monitor CAT efficiency. Has nothing to do with exhaust speed.

Already clarified this. Look above.

Yep, the downstream o2 is only there to monitor CAT efficiency. Has nothing to do with exhaust speed.

Again, look above and re-read my post.

 

[SkullV]

I don't see anything up there but you saying exhaust speed is related to the downstream o2. DBEST seems to have read it the same way I did.

 

[yoffer]

I don't see anything up there but you saying exhaust speed is related to the downstream o2. DBEST seems to have read it the same way I did.

I said i was under the assumption as to why it throws a CEL after a test pipe isntall. I never said it was correct. You simply stated the same thing DBEST did. No need for the same information to be posted twice.

 

[ZLEB]

The reson for the CEL is not because the exhaust moves to fast to read, that's completely false. The front 02 reads the air fuel ratio and relays it back to the engine constantly so it can adjust the fueling constantly. The rear 02 checks the exhaust again to make sure the catalytic converter burned up what the engine didn't. It monitors tha cat effeciency. You get a check engine light because you removed/downgraded the cat from OEM and its boy as clean and efficient anymore. The point of the spacer is so only a small bit of the exhaust makes it to the rear sensor so it's tricked it into thinking a small sample is clean exhaust.

Recently my car self cleared the below efficiency fault on its own also it passed the readiness even thought i'm running a catless d/p with out a spacer on the stock tune . Should i be concerned or just consider myself lucky ? Thanks in advance

 

[DBESTGTI1]

I said i was under the assumption as to why it throws a CEL after a test pipe isntall. I never said it was correct. You simply stated the same thing DBEST did. No need for the same information to be posted twice.

There's also no need to make posts whining when you give wrong info and someone corrects it.... yet here you are... again

 

[DBESTGTI1]

Recently my car self cleared the below efficiency fault on its own also it passed the readiness even thought i'm running a catless d/p with out a spacer on the stock tune . Should i be concerned or just consider myself lucky ? Thanks in advance

It will come back on.

 

[ZLEB]

It will come back on.

That's what i figured thanks again

 

[DBESTGTI1]

Yeah when car is hot and your cruising along around 2000ish-3000ish rpm at steady speed (highways, main roads when you don't catch red lights, that sort of stuff) the car will self test the cat every time the parameters to test itself are met. The light may be gone but I'd bet there is still a fault in the ECM for sporadic cat efficiency. It's going to test itself over and over forever, it will throw the light again, it's just a matter of time (usually not real long)

 

[yoffer]

There's also no need to make posts whining when you give wrong info and someone corrects it.... yet here you are... again

Never said I was right, Dick.

Sent from my Desire HD using Tapatalk 2

 

[DBESTGTI1]

Then it's even less of reason to piss and moan when someone corrects it and posts up what IS right. Seriously, you posted your assuming, I posted fact, SkullV backed up the fact. quite crying about it, stfu, learn something, and move on.

 

[lilfleck]

Both of you stop?? This kind of bickering takes a lot away from the forum.

 

[mcgti6]

yeah.... im still waitin to here some more answers to my original post haha.

Dbest,

can u tell me if u know if the CEL from the cat not being there causes the car to run lean/rich?

or does my stage 2 apr flash make the car run how it should and i just need a spacer or fault-code erase program?

 

[mcgti6]

nvm on that first question of my last post. i just read one of your replies to someone else.