[chickendeluxe]

2003 V6 4x4 Exhaust Manifold w/Cat...HELP!

I'm new to mechanically servicing my Frontiers, but the time has come.

Engine is in Limp Mode from Cats being bad. My mechanic friend claims my truck has exhaust manifolds with integral cats. So it has front and rear cats. We believe all Cats need relaced as this was a work truck with 148K.

Soooooo.....I need advice on what to replace and where to buy. We don't know of any way to trick the computer with an O2 sensor flash or reprogram and install non-Cat Manifolds or Headers.

Thanks, Chris.

 

[joefrontier2]

You have four cats. And 02 sensor before and after the first cat and then a second cat. Unless the 2nd cats are blown you should not have to replace them. If they are blown you can replace them with a straight pipe as they are not needed unless you get inspected.

Pull all code. Your ECU will tell you which O2 is bad.

Why do you think you need cats anyhow.

Bad cats are a rare problem, O2 sensors being bad is probably more of the issue.

 

[massbaster]

Dude Contact Me

i have just fixed this issue for the time being and i just got my inspection sticker here in massachusetts, which is almost as tough as california.

i have tricked the O2 sensors and havent replaced any of my cats.

i have a 2004 crew cab long bed super charge.

pretty much the same model. i also just found out from removing the heat shield that i also have the manifold and cat as one. I AM GLAD!!!! YOU SHOULD BE TOO!!!!! it will cost you around 3-400 dollars i think for all of your parts to do both left and right side.

i have a lot of thought and opinions on what i want to do and what i need to do. i will be removing the second cats and going with straight pipe and i will also replace the manifold and keep stock design since it is 600$+ cheaper.


i could write forever here. might be better to call at some point.
let me know

just know this, for the cost to have nissan do it you could put your self thru welding school and do it your self and still be cheaper.

 

[chickendeluxe]

Probs

The truck was deployed out of state and is getting needed service including timing belt, water pump and LCA's. The truck shows the bad O2 sensor codes and there is a nasty rattle in the manifolds like the converter is breaking apart. I can get the exact codes. The truck is in limp mode.

I've found the manifolds for $315 and $285 from the local dealer. After pulling the heat shield to verify and having the dealer check for the correct manifolds via my VIN, they are the ones with the integral cat, I'm unsure why this is preferred rather than the cheaper manifolds with independent cats after the Ypipe. Is this because I can run a freer flowing exhaust without the rear cats?



I could call if ou PM me. I am interested in your tricks.

C

 

[massbaster]

check this out

140 Manifold :: Engine Mechanical :: Genuine Nissan Parts :: Frontier Parts (D22U) 1998-2004 :: Nissan Parts, NISMO and Nissan Accessories - Courtesyparts.com

this is what i have found for mine. about halfway down the page you will see the labels in a small square box for the cats/manifold. part number 14002 and 14004.

one is 137$ and the other is 129$ if i remember you have the same ones i have.

still need gaskets and what not.

and even though the manifolds maybe cheaper, the cats end up being 500$+ each.
i have been doing a lot of research to the different setups for at least my year engine. the service manual i have breaks down all of the parts for me to match up with on my truck and actually we run a vg33e engine with manifold+cats as one. the 4 cylinder and the vg33er you can just buy cats for w/o replacing your manifold. but the cats are expensive.

 

[chickendeluxe]

Part #'s

Spoke to Courtesy today. My Manifolds are labelled 14002 a14004 as seen with heat shield off.

What I came up with, from Mitch and Cody at Courtesy, is that I need the manifold/cat assembley superceded with :

PN 208A0-WD22004 and
PN 208A1-WD22004

They sell them for $515 retail is $821 ea! Woof!

We caught the local dealer today and they say they can do them for $314 nad $282. That is manifold w Cat and install stuff. I hope this is the correct stuff. I will replace my O2 Sensors as well.

I have seen on a bunch of sites manifolds available for less than $100 but didn't know what to do about o2 readings and Marylad emmissions. If the computer could be fooled I can use less expensive manifolds, retain O2 sensors and register this in a Non Emmissions state.

C

 

[massbaster]

Spoke to Courtesy today. My Manifolds are labelled 14002 a14004 as seen with heat shield off.

What I came up with, from Mitch and Cody at Courtesy, is that I need the manifold/cat assembley superceded with :

PN 208A0-WD22004 and
PN 208A1-WD22004

They sell them for $515 retail is $821 ea! Woof!

We caught the local dealer today and they say they can do them for $314 nad $282. That is manifold w Cat and install stuff. I hope this is the correct stuff. I will replace my O2 Sensors as well.

I have seen on a bunch of sites manifolds available for less than $100 but didn't know what to do about o2 readings and Marylad emmissions. If the computer could be fooled I can use less expensive manifolds, retain O2 sensors and register this in a Non Emmissions state.

C

so courtesy parts said either get the manifold and cat seperately and pay big bucks thru the nose? or you can get the manifold and cats as one piece for under 140.00 each?

thats what i am seeing. sure i could replace the manifolds with ones for bolt on cats but thats way more expensive to do now and any other time that the cat may need to be replaced.(515/821$)

getting the primary cat out is gonna take just about as much work as to replace the manifold anyways. alittle care and a lot of soak time with some good penetrating spray and your manifold bolts should come right out.

if your looking to trick your CEL lite off then you need to space out your O2 sensors. Your cats are still bad if you are getting P0430/p0420 codes.

be less concerned about your sensors and more concerned about your cats.

cats clean the O2 from the exhaust stream with activated type carbon interior. as this gets full and saturated, more O2 gets thru and that is what your sensor sees. that in turn causes changes to be made to the computer and the engine light to come on.

all i was able to do was to get my light to turn off on its own so i could get a sticker and later when its warmer, i can work on the exhaust. right now i am pricing things out and waying my options.

also if you have found anything as cheap as what i have seen, then please send a link. also check those courtesy guys again. not sure they being totally accurate. from what i see on the web site and that page your 2003 v6 parts are the cheap ones. all the other parts listed are for different years and models.

headers arent a bad idea with straight pipes. there is someone here that has done it but they certainly arent plug and play. probably better to learn how to weld and get non cat manifolds and make rest of exhaust. of course you still need to space out your O2 sensors.


$5 o2 cheater/non fouler how-to - evolutionm.net

this is a link that i kinda followed. although i changed things slightly.

here is something i just found.
Scion tC Anti-Fouler

although i cant see if its 18mm or not.

there is another right angle one that i have seen but i cant find the link

i know these are for different cars , but the main point is to move your o2 sensor out of the exhaust stream. the sensor itself is 1/2 inch in diameter and the threads are 18mm.

 

[massbaster]

Spoke to Courtesy today. My Manifolds are labelled 14002 a14004 as seen with heat shield off.

What I came up with, from Mitch and Cody at Courtesy, is that I need the manifold/cat assembley superceded with :

PN 208A0-WD22004 and
PN 208A1-WD22004

They sell them for $515 retail is $821 ea! Woof!

We caught the local dealer today and they say they can do them for $314 nad $282. That is manifold w Cat and install stuff. I hope this is the correct stuff. I will replace my O2 Sensors as well.

I have seen on a bunch of sites manifolds available for less than $100 but didn't know what to do about o2 readings and Marylad emmissions. If the computer could be fooled I can use less expensive manifolds, retain O2 sensors and register this in a Non Emmissions state.

C

i tried searching thier site for those part numbers and didnt find anything. from the link i gave you it will all depend if you have the s/c xe or se. i cant understand why they wouldnt be interchangeable. and i cant understand what the guys at courtsey nissan are telling you

 

[joefrontier2]

Whatever you guys do make sure you get the manifolds that have been upgraded for the 2003 and 2004 model years by Nissan (no telling what they will try and sell you at a dealer or online). These year should be usable on all model engines (but you may want to check).

The reason I say this is that the 2002 and earlier are prone to failure. All the guys that are 2002 and earlier have had this problem. There are some earlier 2003 models that have this too as their manifolds were 2002 old stock.