really dumb question

cbjones26 · Post by **cbjones26** » Mon Mar 24, 2008 12:08 am

ok i have a 2000 Plymouth neon, the cat converter was plugged and i gutted it as i was under the car i noticed both o2 sensors where before the converter an the upstream one was like in the header or part of it so it looks , why is this? i was going to get a replacement converter from modern performance but the location for the o2 sensor is behind the cat. an i notice in another post that someone said something about a resonator where is this located bc i dont think my car has one

Post by **occasional demons** » Mon Mar 24, 2008 1:05 pm

I have seen the downstream in the center of the cat but not before it. Do you have a CEL? Does it have the flange that bolts to the manifold or has it been rewelded that you can tell? Possibly the cat was installed backwards?

cbjones26 · Post by **cbjones26** » Mon Mar 24, 2008 2:01 pm

umm.. they both are before the converter an its the original converter or it appears to be. what is a cel?

here is the web addy for my cardomain page i have a pic of it on there.

http://www.cardomain.com/ride/3010936

JJS66 · Post by **JJS66** » Mon Mar 24, 2008 2:10 pm

Just for reference or comparison the stock exhaust on my 00 Plymouth Neon has the downstream after the cat. Upstream is located as you describe. No resonator on mine as well.

cbjones26 · Post by **cbjones26** » Mon Mar 24, 2008 2:11 pm

i think i got a messed up car!! :/

Post by **occasional demons** » Mon Mar 24, 2008 3:33 pm

A CEL is check engine light. That is definitely strange. but I haven't seen a 2000 to know how they were setup, so I can't say.

cbjones26 · Post by **cbjones26** » Mon Mar 24, 2008 3:45 pm

ya the cel is on for cat. inefficacy, well that was the code before i gutted it! an its still on which i fig it would be. if u get a chance can u look at the pic i have on cardomain.com maybe that will help with what im talking about. the o2 sensor u can see in the pic is the downstream one

JCsrt04 · Post by **JCsrt04** » Mon Mar 24, 2008 8:36 pm

did you buy it used? seems like someone had a bung welded in for a wideband o2 sensor

cbjones26 · Post by **cbjones26** » Tue Mar 25, 2008 4:15 pm

the car is used yes. what does a wide band o2 sensor do? will a 18mm Spark Plug Non-Fouler work with the way this is set up to get the cel off? so it will pass ny state inspection?

Post by **occasional demons** » Tue Mar 25, 2008 9:05 pm

I doubt it will pass inspection. You will need to install the o2 behind/in the cat. If you get the replacement there will be a bung in the proper location.
I found this searching and it looks like your set up I can't figure how this works with the down steam before the cat. You can clearly see the upstream in the manifold. this looks like factory set up. They both will read close to the same setting a CEL.
http://forum.2gn.org/viewtopic.php?t=31 ... +converter
Some where on here there is a pic of the cat with the bung in the middle and one with it in the end but I'm not getting the proper word combo to find it.
Edit:
http://www.car-stuff.com/mmparts/dodge- ... erter.html

If your mani looks like this it is the standard emmisions unit. I can't find any pics of the ULEV ones that have the cat built in. Possibly someone installed the wrong cat on your car, or the manifold was swapped.
http://cgi.ebay.com/ebaymotors/Dorman-E ... enameZWDVW

cbjones26 · Post by **cbjones26** » Wed Mar 26, 2008 2:23 am

what if i just replace the whole exhaust? i kinda dont want to have a cat. bc the power gain i got from gutting it.. i mean shit one my way to work i pulled up to a red light an some punk kid in a mid -late 90's civic with a bunch shit on it,( exhaust body kit etc) started laughing an did the lil head nod like he wanted to race so i though fuck it why not.. not only did my car launch like a rocket off the line this poor kid coulndt even catch me at the next red light when he pulled up he was shaken his head!! stock 00 Plymouth atx neon vs 90's civic slightly moded winner the neon! i love killing the lil jap cars!!!..

i was thinking this header

http://www.modernperformance.com/produc ... 378abc55ba

this cat

http://www.modernperformance.com/produc ... 378abc55ba

not sure about muffler i dont want a dual exhaust was thinking about going with a borla muffler or maybe a flowmaster!

i want a good sound but some hp/tq gains if i can!!

if i do this though im not sure where to put the upstream o2? an if the down stream will even reach to the spot on that converter.

or i could go with just this cat

http://www.partsamerica.com/productdeta ... 45&PTSet=A