O2/Cat converter help please.

[DallasJones]

Hi guys,

I'm new here but I'd really like some help with my DC5R. I bought this car in January and it had all sorts of problems. Thankfully I've got them all sorted except one - the exhaust system. This is my first tuner and I'm still learning quite a bit.

When I bought it, the exhaust tip wasn't even attached. So I got a sports exhaust put on.


My check engine light is on, which gives 3 error codes all related to oxygen sensors. From what I can tell the last owner ripped out the cat converter, unplugged both oxygen sensors and had a dodgy welding job done. I've kind of ran out of money now (I'm on trainee wages so saving is quite difficult) and was wondering if I could get some advice on what I should do. I'm not sure where the front sensor plugs into or where to get a plug. I've figured out the back sensor is meant to plug into the cat.

Has anyone got any advice for me? What are my options? I think my cheapest option to make this legal would be to acquire the o2 sensor plugs and solder them in, plug the front one in to wherever it goes, purchase a high flow cat converter online (A recommendation would be nice) and get my local exhaust guys to repair it.

Normally I would go straight to them and get it all sorted properly but they quoted $1000 which I simply don't have. I'm also paying $80 dollars a week in fuel at the moment driving to work so it'd be great if I could sort this out soon for a better fuel economy.


As I'm new to the site and I'm already after help, I'll contribute by making a few guides on projects I've done. It's all I can really offer. But others might find them useful.


Here are some photos:

The current dodgy setup. http://i.imgur.com/Yqxuz.jpg
The fault codes. http://i.imgur.com/hwc6m.png

 

[C&S Evo7]

Hi Dallas,
ok some questions-
- what exhaust headers are fitted?
- what decat pipe is fitted?

In the pictures the lambda sensors are too close together,, the front one should be at the end of the header ( looks about right from your pictures and should plug in to a wire hanging from the bulkhead I think, the primary sensor does most of the fuel adjustments

The rear sensor would normally be after the cat and really only is there to check that the cat is working.

On a dc5 R the front sensor and rear sensor are different, the Oem front is a wideband one.

Even if you replace the sensors ( my recommendation) which will cost about $450 you will probably still get the ecu light, there are two ways around this,
- refit a cat you could always get an second hand one from here
- get an O2 sensor simulator

 

[DallasJones]

Thanks for the quick reply. Here's a picture of what's in front of the front sensor which is quite close to the extractors. These were on there, I just know they're aftermarket racing extractors. http://i.imgur.com/ts9XP.jpg

As far as I know there isn't a decat pipe. The cat converter was just removed and that's why the sensors are so close together. That helps a lot though, so my options are:

1. Replace both sensors and add a high flow cat converter (Or a standard second hand one to save some money) for a completely legal system.
2. Replace the front sensor, get the leaking exhaust welded up properly and get a rear o2 sensor simulator.

Sorry if I sound retarded, this is all very new to me.

 

[C&S Evo7]

Ah ok, that looks like a typical race header so yes there's no cat, I would think it will be quite difficult to retrofit a race cat as they are normally pretty much where your extractors join. It would prob be better to get a replacement Oem header and cat second hand

 

[DallasJones]

That sounds like I would lose a lot of performance. I think I'll just go with the o2 replacement/simulator idea. Thanks a lot, I appreciate it.

 

[DallasJones]

Do you think it'd be a good idea to get a cheap cat converter and slam a pipe through it? Just for a bit of legal evasion.