Nissan Primera P11-144 cams |
Post Reply | Page <12 |
Author | |
Dawek
NPOC Guest Joined: 26 Aug 2016 Location: Czech Republic Online Status: Points: 114 |
Post Options
Thanks(0)
|
Ok, got it. Just one more question. What is the reason for moving it out of direct exhaust stream? In stock (when before the main cat) it is mounted in direct exhaust stream, right? So what is the reason to move it out of the exhaust stream? (i'm a newbie, so sorry if it is a stupid question)
|
|
essNchill
Admin Group Nissyen Gaius Fluff Joined: 05 Feb 2003 Location: Hampshire Online Status: Points: 62605 |
Post Options
Thanks(1)
|
An aftermarket manifold doesn't have a pre-cat, so if you fit one on the 144 and leave the second sensor where it is, the readings will be insane :)
|
|
Dawek
NPOC Guest Joined: 26 Aug 2016 Location: Czech Republic Online Status: Points: 114 |
Post Options
Thanks(0)
|
Yeah, i understand that, maybe the question was posed wrong. I was just curious why does the second sensor have to be out of the exhaust stream after it was moved behind the main cat.
|
|
bavs83
NPOC Guest Joined: 26 Dec 2008 Location: Lancashire Online Status: Points: 844 |
Post Options
Thanks(1)
|
The purpose of the pre cat and cat is to clean up the exhaust emissions. The ECU uses the first lambda to detect how much is needed to clean up. The second lambda checks to see if the precast is working and cleaning up as it should. The ECU will adjust the air fuel ratio to help with this. By removing a precat, your reducing the amount the car can clean. By moving the sensor past the main cat and out of direct stream the ECU thinks both cats are working fine and the engine management light won't come on.
If you keep the lambda I the air stream, it may think the engine or cat is a problem and your enine management light will come on. Hope this makes sense......there is more science to this but I've just sumarised it |
|
It's not what you drive....It's how you drive!
|
|
Dawek
NPOC Guest Joined: 26 Aug 2016 Location: Czech Republic Online Status: Points: 114 |
Post Options
Thanks(0)
|
Oh, now I get why it should be moved out of the direct stream. Thanks man, I am looking forward to learning more about how all the stuff works.
|
|
Post Reply | Page <12 |
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |