[tbaig]

I plan on getting a catless downpipe installed this week and won’t be able to install my JB4 until the following week. Are there any concerns/issues with driving with a CEL on?

[morphomeman]

Do you plan to try to pass inspection with no cat? Not in California you won't, or in any state that has decent protocols.
And what makes you want to do this? Will this car be for track use only? What sort of power gain do you imagine you will get? Or is it just the noise that you enjoy?
Does your car have any sort of warrantee coverage? If so, then bye-bye.
Guess you can tell that I am no fan of going catless.

[SteveInfante]

No worries OP. Mechanically you should be fine. May run a little rich till you tune it with the JB4 but that's not going to hurt anything.

[tbaig]

My car has MD plates and I've already passed emissions which is once every two years. I am doing it for the extra power gain. The JB4 should go on soon. Warranty expires in two months as well.

Thanks for the help.

[jmwilson125]

Been doing this for a while without issue. You will enjoy the power and sound from the DP and tune.

I've had a question for a while but never really thought to ask.

When the dp constantly triggers a cel, what happenes if there's some other issue? If your gas cap is loose, then you won't know because the cel is always on.

The reason I haven't really bothered to ask is because I figured,
A. If it's something important like add engine oil, then the idrive screen tells you.
B. If it's something really important like excessive knock lol, the. The jb4 will throw you to map 4 and record faults.
C. If you have the codes auto clear, it only clears the codes periodically. If something happens while driving a cel will pop back up. I.e. start car, tune clears code, drive 10 miles without cel, engine oil needed, cel pops back on.


Is there a concern with always having a cel in this aspect? Or if a tune is clearing codes? Flash tune would specifically suppress do codes, right?

[XutvJet]

Originally Posted by tbaig

I plan on getting a catless downpipe installed this week and won’t be able to install my JB4 until the following week. Are there any concerns/issues with driving with a CEL on?

FYI, the JB4 no longer turns off CELs. I believe someone created a work around, but I believe it's hit/miss.

[mike@x-ph.com]

No concerns car will run fine

[Sail Boat]

Originally Posted by morphomeman

Do you plan to try to pass inspection with no cat? Not in California you won't, or in any state that has decent protocols.
And what makes you want to do this? Will this car be for track use only? What sort of power gain do you imagine you will get? Or is it just the noise that you enjoy?
Does your car have any sort of warrantee coverage? If so, then bye-bye.
Guess you can tell that I am no fan of going catless.

Agree, please buy a catted DP. Yes, they cost more, but you'll be doing your part to help protect our environment, no matter how small that contribution may be.

[SteveInfante]

Originally Posted by Sail Boat

Agree, please buy a catted DP. Yes, they cost more, but you'll be doing your part to help protect our environment, no matter how small that contribution may be.

L O L. ......

[beMtroubleYou]

Originally Posted by Sail Boat

Agree, please buy a catted DP. Yes, they cost more, but you'll be doing your part to help protect our environment, no matter how small that contribution may be.

If you are commutying alot and in lots of jams I would go catted.

Mostly for your own health, that carbon aint healthy to breath in. But yeah. We are destroying this earth with our shit, with that said: I am running catless but I am not doing any mileage on it.

[Tpeterson]

Emissions warranty in Calif. is 150K miles. You can kiss that goodby

[B58togo]

Love the doom & gloom in these types of threads.

FWIW, latest JB4 firmware won’t clear the CEL. Terry had to play nice with the California Air Resources Board to gain certification on the JB4. Sucks the way he snuck it into the last revision without warning anyone first. People are having good luck with running a spacer on the second O2 sensor though.

[Sail Boat]

Originally Posted by B58togo

Love the doom & gloom in these types of threads.

FWIW, latest JB4 firmware won’t clear the CEL. Terry had to play nice with the California Air Resources Board to gain certification on the JB4. Sucks the way he snuck it into the last revision without warning anyone first. People are having good luck with running a spacer on the second O2 sensor though.

It isn't "doom & gloom", it is a choice.

Considering ethics and facts, the omission of a catalytic converter on a street car is a conscious and illegal choice to be less responsible.

[Maynard]

Not that I haven't removed a few cat's back in the day, but that was back when they cost you 20-40 hp easy (sometimes closer to 100), and there were no real hi-po alternatives. Nowadays, driving catless in SoCal is a rather jerk move given the alternatives - how much Hp does it cost to stick with a catted version?

And losing legality and warranty coverage are not 'gloom and doom' - they should be expected. Might also want to check your fine print on your car insurance, as some will have a loophole that will leave you uncovered in any kind of serious accident (especially if you don't really maintain a residence in the 'home state' that issued your plates).

[TajoMan]

how much hp gain we are talking?
just curious.

Also, I would be surprised if there is no CEL without cat. what's the O2 sensor for?
FYI, most of the CEL is due to emission related problem.
I cannot believe it does not throw CEL without cat. (unless the O2 sensor is tricked somehow)

[B58togo]

Originally Posted by Sail Boat

It isn't "doom & gloom", it is a choice.

Considering ethics and facts, the omission of a catalytic converter on a street car is a conscious and illegal choice to be less responsible.

My doom & gloom reference was in response to the textbook concerns about the car not running right, warranties being voided and cars with catless dp’s bursting into raging fireballs on a death spiral, deep into the bowels of hell.

Had nothing to do with your noble attempt to save the world. Get over yourself.

[Sail Boat]

Originally Posted by B58togo

My doom & gloom reference was in response to the textbook concerns about the car not running right, warranties being voided and cars with catless dp’s bursting into raging fireballs on a death spiral, deep into the bowels of hell.

Had nothing to do with your noble attempt to save the world. Get over yourself.

Fun! It's always a pleasure arguing with you, B58togo.

Your hyperbole and contempt aside, these "textbook concerns" are nevertheless legitimate concerns. Furthermore, you must understand that the "textbook concerns" you defined under your definition of "doom & gloom" and the conspicuous environmental and legal ramifications of removing a catalytic converter are not mutually exclusive. Therefore, your definition of "doom & gloom", notwithstanding the progression of the thread and your implicative appreciations, is dreadfully imperceptive.

[tbaig]

Originally Posted by XutvJet

FYI, the JB4 no longer turns off CELs. I believe someone created a work around, but I believe it's hit/miss.

There is a thread with the workaround. Going to give that a shot one i get my JB4 back on.

[tbaig]

Last question, will the JB4 clear the CEL if i install it AFTER the dp?

[Maynard]

Used to be that when you got into modding your car, it involved manning up and accepting that you were now neither legal nor safe. Hate to say it, but that was probably part of the fun (that and doubling your Hp in a weekend of wrenching). Now I guess it is just 'write the check, affix snowflake sticker to the back window, and hope all the haters get over themselves before they say something mean'.

[morphomeman]

OP has still not told us what increase he expects in HP or torque from going CATless.
With modern engines , there may be minimal gain.
Inquiring minds want to know.

[SteveInfante]

Ha ha ha...I like your sense of humor.