Engine Thermal Expansion or Clicking/Knocking/Pinging
#16
Super Moderator
Actually that fan is the belt driven cooling fan on the radiator. The emission air pump fan only runs during cold starts.
Here are some of tecman's pictures of it. This is under that cover over the radiator but in pics notice the windshield washer fluid fill for orientation
https://www.clublexus.com/forums/gx-...ml#post9903088
Here are some of tecman's pictures of it. This is under that cover over the radiator but in pics notice the windshield washer fluid fill for orientation
https://www.clublexus.com/forums/gx-...ml#post9903088
#18
Super Moderator
Only if I turn off everything and explicitly listen for it.
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nastron (05-19-19)
#19
Driver School Candidate
Thread Starter
Gotcha. I'm kinda more convinced now that it's probably not a problem and all I'm hearing is probably thermal expansion or something, especially since this system throws a code or even more if any kind of failure occurs with it. I'm just being **** with this since my previous 2012 RX 350 had me at the dealership most of my weekends during the last 2 or 3 months of ownership.
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Acrad (05-19-19)
#20
Super Moderator
I hear ya... I get the same way about things like that.
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nastron (05-19-19)
#22
Driver School Candidate
Thread Starter
Check this out Acrad35751, I was just double checking the noise outside in my garage and I noticed this other strange noise that I think is coming from that same air pump when I shut off the engine:
That's definitely not normal right?
That's definitely not normal right?
Last edited by Acrad; 05-21-23 at 01:53 AM.
#23
Super Moderator
Let me look around some. I thought they changed the logic on '14+ to possibly have a shutdown cycle with the air pump.
Any other '14+ owners hear this on shutdown?
The Hewitt-Tech owner user (HewittTech) might be able to chime in as well.
Any other '14+ owners hear this on shutdown?
The Hewitt-Tech owner user (HewittTech) might be able to chime in as well.
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nastron (05-19-19)
#24
The sound you are hearing when you start it up sounds more like an exhaust tick to me. Really hard to tell without hearing it in person.
On startup the secondary air pump is more like a whine, runs 30 second to a minute and and then you may the air switching valves close and the whine go away. On some vehicles it is more noticeable than others. For instance, you typically don't hear the pumps run on the 5.7l or 4.7l unless they are failing because they are isolated under the intake or inside the passenger front fender. The 4.0 and 4.6l usually have the pump just under the hood so they are more noticeable.
The noise you are hearing on shutdown in the clip is absolutely the secondary air system. As far as i am aware all 2015 and newer vehicles will run the air pump at shutdown. All 2013 and newer 4.0l run at shutdown. There is a possibility with a certain reflash certain 2012 and 2013 5.7l can but most don't but all flex fuel 5.7l vehicles do.
The system running at shutdown is why our current V3 and V5 units only half work on those vehicles. On those vehicles that run the system at shutdown they still stop the system from running on startup but can't prevent it from running at shutdown. This is where our soon to be released Second Generation bypass kits will take over and cover up to the current model year. Instead of just preventing the system from running we essentially simulate it so the computer thinks everything is functioning as it should. This also eliminates the need to keep most of the system on the vehicle.
We are trying hard to get our production caught up and able to produce the new units as well. We manufacture everything in house so it takes a little longer but we hope to have the Next Gen units available this summer, summer 2019.
Please contact us directly by email or phone for more information or inquiries about our current or next gen bypass kits for the secondary air system on these vehicles.
On startup the secondary air pump is more like a whine, runs 30 second to a minute and and then you may the air switching valves close and the whine go away. On some vehicles it is more noticeable than others. For instance, you typically don't hear the pumps run on the 5.7l or 4.7l unless they are failing because they are isolated under the intake or inside the passenger front fender. The 4.0 and 4.6l usually have the pump just under the hood so they are more noticeable.
The noise you are hearing on shutdown in the clip is absolutely the secondary air system. As far as i am aware all 2015 and newer vehicles will run the air pump at shutdown. All 2013 and newer 4.0l run at shutdown. There is a possibility with a certain reflash certain 2012 and 2013 5.7l can but most don't but all flex fuel 5.7l vehicles do.
The system running at shutdown is why our current V3 and V5 units only half work on those vehicles. On those vehicles that run the system at shutdown they still stop the system from running on startup but can't prevent it from running at shutdown. This is where our soon to be released Second Generation bypass kits will take over and cover up to the current model year. Instead of just preventing the system from running we essentially simulate it so the computer thinks everything is functioning as it should. This also eliminates the need to keep most of the system on the vehicle.
We are trying hard to get our production caught up and able to produce the new units as well. We manufacture everything in house so it takes a little longer but we hope to have the Next Gen units available this summer, summer 2019.
Please contact us directly by email or phone for more information or inquiries about our current or next gen bypass kits for the secondary air system on these vehicles.
#25
Why did Lexus have this system run on shutdown starting with 2015 with the well known history here? What is the reason for this?
#26
I think it is to blow any residual moisture out of the system. This prevents water collecting in the pump that can damage the vanes and the valves from freezing closed with ice. They also added a pump heater to the system to drive moisture out of the pump motor. Will it help? Time will tell.
#27
Super Moderator
Do you know if the 10-13 models which are fixed under the warranty extension get this version of air pump with heater?
#28
#29
Driver School Candidate
Thread Starter
The sound you are hearing when you start it up sounds more like an exhaust tick to me. Really hard to tell without hearing it in person.
On startup the secondary air pump is more like a whine, runs 30 second to a minute and and then you may the air switching valves close and the whine go away. On some vehicles it is more noticeable than others. For instance, you typically don't hear the pumps run on the 5.7l or 4.7l unless they are failing because they are isolated under the intake or inside the passenger front fender. The 4.0 and 4.6l usually have the pump just under the hood so they are more noticeable.
The noise you are hearing on shutdown in the clip is absolutely the secondary air system. As far as i am aware all 2015 and newer vehicles will run the air pump at shutdown. All 2013 and newer 4.0l run at shutdown. There is a possibility with a certain reflash certain 2012 and 2013 5.7l can but most don't but all flex fuel 5.7l vehicles do.
The system running at shutdown is why our current V3 and V5 units only half work on those vehicles. On those vehicles that run the system at shutdown they still stop the system from running on startup but can't prevent it from running at shutdown. This is where our soon to be released Second Generation bypass kits will take over and cover up to the current model year. Instead of just preventing the system from running we essentially simulate it so the computer thinks everything is functioning as it should. This also eliminates the need to keep most of the system on the vehicle.
We are trying hard to get our production caught up and able to produce the new units as well. We manufacture everything in house so it takes a little longer but we hope to have the Next Gen units available this summer, summer 2019.
Please contact us directly by email or phone for more information or inquiries about our current or next gen bypass kits for the secondary air system on these vehicles.
On startup the secondary air pump is more like a whine, runs 30 second to a minute and and then you may the air switching valves close and the whine go away. On some vehicles it is more noticeable than others. For instance, you typically don't hear the pumps run on the 5.7l or 4.7l unless they are failing because they are isolated under the intake or inside the passenger front fender. The 4.0 and 4.6l usually have the pump just under the hood so they are more noticeable.
The noise you are hearing on shutdown in the clip is absolutely the secondary air system. As far as i am aware all 2015 and newer vehicles will run the air pump at shutdown. All 2013 and newer 4.0l run at shutdown. There is a possibility with a certain reflash certain 2012 and 2013 5.7l can but most don't but all flex fuel 5.7l vehicles do.
The system running at shutdown is why our current V3 and V5 units only half work on those vehicles. On those vehicles that run the system at shutdown they still stop the system from running on startup but can't prevent it from running at shutdown. This is where our soon to be released Second Generation bypass kits will take over and cover up to the current model year. Instead of just preventing the system from running we essentially simulate it so the computer thinks everything is functioning as it should. This also eliminates the need to keep most of the system on the vehicle.
We are trying hard to get our production caught up and able to produce the new units as well. We manufacture everything in house so it takes a little longer but we hope to have the Next Gen units available this summer, summer 2019.
Please contact us directly by email or phone for more information or inquiries about our current or next gen bypass kits for the secondary air system on these vehicles.
Last edited by nastron; 05-20-19 at 06:56 AM.
#30
my 2012 does the shut down pump thing ever since i got the pump changed and box flashed. they did say it was to get moisture out in an attempt to not have more issues. they also told me that none that have had this fix have had to come back. i spose i should add 'yet'.