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SAI... disabled but not removed, or removed, or do not touch ? ?

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Old Apr 23, 2026 | 07:43 PM
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Question SAI... disabled but not removed, or removed, or do not touch ? ?

Hi. Has anyone deleted the SAI ? Any computer error codes appear ? If its fan motor dies or gets disconnected; what is affected ?
I was reading this article, pasted below :
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Can You Drive Without the Secondary Air Injection System?

How does it affect the vehicle if the secondary air injection system is not working properly? Mechanically speaking, the secondary air injection system only affects post-combustion operations, and so a nonfunctioning SAIS doesn’t impact engine performance or fuel economy. Therefore, the sole function of the SIAS is emission reduction. That said, the SAIS will only run on a cold start when the vehicle has been sitting for at least seven hours. Even then, it will only run for 30 to 90 seconds to allow the operating temperature to be reached.

It would be more accurate to state that the SAIS reduces emissions at most once every seven hours for 30 to 90 seconds. Outside of that specific time period, the SAIS is inactive. Consequently, if the secondary air injection system is not working properly, exhaust will be richer after a cold start until operating temperature is reached. Unfortunately, there are certain secondary air injection system error codes that can put the vehicle into “limp mode,” which is a reduced performance mode where power and acceleration are limited "
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Old Apr 26, 2026 | 11:41 AM
  #2  
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From: Whidbey Island, PNW
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Originally Posted by Externet
Hi. Has anyone deleted the SAI ? Any computer error codes appear ? If its fan motor dies or gets disconnected; what is affected ?
I was reading this article, pasted below :
================================================== =======================

Can You Drive Without the Secondary Air Injection System?

How does it affect the vehicle if the secondary air injection system is not working properly? Mechanically speaking, the secondary air injection system only affects post-combustion operations, and so a nonfunctioning SAIS doesn’t impact engine performance or fuel economy. Therefore, the sole function of the SIAS is emission reduction. That said, the SAIS will only run on a cold start when the vehicle has been sitting for at least seven hours. Even then, it will only run for 30 to 90 seconds to allow the operating temperature to be reached.

It would be more accurate to state that the SAIS reduces emissions at most once every seven hours for 30 to 90 seconds. Outside of that specific time period, the SAIS is inactive. Consequently, if the secondary air injection system is not working properly, exhaust will be richer after a cold start until operating temperature is reached. Unfortunately, there are certain secondary air injection system error codes that can put the vehicle into “limp mode,” which is a reduced performance mode where power and acceleration are limited "
================================================== ========================
First off, these types of plugs work well -

You will get a code and Check Engine light. In my experience, it doesn’t put the truck in any “limp mode” on a D2. This thread explains (BCU/ECU replacement the best way, I’ve never had luck coding it to UK/EU via Nanocom). https://landroverforums.com/forum/di...es-how-116896/

BTW - not true that it only operates when the vehicle has been sitting for 7 hours on a D2, but that’s relatively unimportant detail.

 
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