Smog/A.I.R pump delete
Racer
Joined: Apr 2018
Posts: 349
Likes: 55
Closed vs open loop is just the difference in how the computer uses the information it has available. Closed loop offers usable 02 input for fuel trimming, so that computer does that. Some people run open loop only tunes, so 02 is never used.
I think closed loop also does some egr stuff, as well as chang where the AIR system is blowing, but I don't have either anymore.
Team Owner
Joined: Sep 2001
Posts: 62,160
Likes: 1,733
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
This is getting interesting ...
Sorry for the stoopid question , but what happens if the car drops into open loop ?
I just got a pair of Hedman's and I am about to ditch the air sistem and install the headers .
Also I've seen that those heated sensors have 2 wires . My 85 has only one .
Any ideea on where to plug the second sensor wire ?
Thanks.
Sorry for the stoopid question , but what happens if the car drops into open loop ?
I just got a pair of Hedman's and I am about to ditch the air sistem and install the headers .
Also I've seen that those heated sensors have 2 wires . My 85 has only one .
Any ideea on where to plug the second sensor wire ?
Thanks.
In open loop, its basically reading the TPS and the coolant temps and going off pre-programmed tables of how long to leave the injectors open. This will end up being richer, much richer in my case. If the exhaust is very rich, that fuel doesnt burn clean, and you dump a lot of soot and other particulates into the cats, which clog it up. They'll never really burn out.
At WOT, the ECM is going off programmed tables. This is why tuning is done on a dyno with a good (or two good) O2 sensors to get that part right, since its in the chip forever.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Single wire has only sensor data. No power to it and no ground since the threads are the ground. 3 wire sensor has a heater and a ground. 4 wire has heater, 2 grounds and sensor data.
Heel & Toe
Joined: Apr 2017
Posts: 19
Likes: 1
I also did a smog delete on my L98. I'll try to answer your questions as best I can.
I put long tube headers on the car, so I didn't have the AIR tubes on the exhaust manifold. However, the check valves on the air tubes (the parts that connect the manifold and the rubber air line coming to the manifold) actually are a 'cap' on the manifold. So if you pull the rubber lines off, you will effectively have capped the headers.
I also deleted my cat with this project, so the AIR line to it is gone as well. If I remeber correctly, it wad crimped or welded on. So you could buy a new cat without air hookup (expensive and hard), or you can cut the air line and weld it shut at the cat. Finally, you could leave the line run to the cat, since there is a check valve for this line on the passenger side of the engine bay. This would be easiest.
As for connections, you can remove all of the air system, including the solenoids and the metal and rubber lines. The connectors for the solenoids can be taped up or cut off and taped, the vacuum line can be plugged.
I put long tube headers on the car, so I didn't have the AIR tubes on the exhaust manifold. However, the check valves on the air tubes (the parts that connect the manifold and the rubber air line coming to the manifold) actually are a 'cap' on the manifold. So if you pull the rubber lines off, you will effectively have capped the headers.
I also deleted my cat with this project, so the AIR line to it is gone as well. If I remeber correctly, it wad crimped or welded on. So you could buy a new cat without air hookup (expensive and hard), or you can cut the air line and weld it shut at the cat. Finally, you could leave the line run to the cat, since there is a check valve for this line on the passenger side of the engine bay. This would be easiest.
As for connections, you can remove all of the air system, including the solenoids and the metal and rubber lines. The connectors for the solenoids can be taped up or cut off and taped, the vacuum line can be plugged.
valves. What did you do with those? Lastly, there is a large air line left
that I cant see where it goes no matter how I angle.. It was attached to one of the check valves right next to the water pump and runs straight down towards the crank. How did you remove this one? Thanks for any help you can provide.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Its a T-connection that runs under the plenum and connects to the fuel pressure reg and then to the rear of the manifold.. Do I cap those? or do I have to make a new vacuum connection?
Also the electrical connections to the air system.. I think they are called check valves. What did you do with those?
Lastly, there is a large air line left that I cant see where it goes no matter how I angle.. It was attached to one of the check valves right next to the water pump and runs straight down towards the crank. How did you remove this one? Thanks for any help you can provide.
Also the electrical connections to the air system.. I think they are called check valves. What did you do with those?
Lastly, there is a large air line left that I cant see where it goes no matter how I angle.. It was attached to one of the check valves right next to the water pump and runs straight down towards the crank. How did you remove this one? Thanks for any help you can provide.
I don't think that is what they are called. If it is electrical, I would just tape it off. Drive it for a bit and when you are satisfied, you can do a more detailed tape off or even cut the ends off and tape the ends.
I have a feeling it runs down to the cat. Cut it off and plug the tube in the cat.
Racer
Joined: Apr 2018
Posts: 349
Likes: 55
Thank you for replying.. I followed what you said and I just have a few more obstacles, if you could help that would be great. There was a vacuum line connected to the air system that I don't know what to do with... Its a T-connection that runs under the plenum and connects to the fuel pressure reg and then to the rear of the manifold.. Do I cap those? or do I have to make a new vacuum connection? Also the electrical connections to the air system.. I think they are called check
valves. What did you do with those? Lastly, there is a large air line left
that I cant see where it goes no matter how I angle.. It was attached to one of the check valves right next to the water pump and runs straight down towards the crank. How did you remove this one? Thanks for any help you can provide.
valves. What did you do with those? Lastly, there is a large air line left
that I cant see where it goes no matter how I angle.. It was attached to one of the check valves right next to the water pump and runs straight down towards the crank. How did you remove this one? Thanks for any help you can provide.
The tube going down is where the AIR system diverts air that isn't used in the headers/cats - it is a silencer valve, I left mine on. It just goes down to a baffle, so you won't hear the air rush out. It is just waste air.
Heel & Toe
Joined: Apr 2017
Posts: 19
Likes: 1
A pair of golf tees to plug the T connector. The electrical connectors aren't check valves. I think there was one for each solenoid, two connectors total. Just tape them off with electrical tape.
The tube going down is where the AIR system diverts air that isn't used in the headers/cats - it is a silencer valve, I left mine on. It just goes down to a baffle, so you won't hear the air rush out. It is just waste air.
The tube going down is where the AIR system diverts air that isn't used in the headers/cats - it is a silencer valve, I left mine on. It just goes down to a baffle, so you won't hear the air rush out. It is just waste air.
summer after all.. Did you cap the silencer valve or just leave it open?
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
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Racer
Joined: Apr 2018
Posts: 349
Likes: 55
I'm glad I could help! It is a great feeling to get your car up and running as the nice weather hits, lets you really enjoy it!
1st Gear
Joined: Sep 2019
Posts: 1
Likes: 0
Quetion for 65Z01
You don't mention the year but I assume a L98 due to the presence of the damn AIR system.
You can look at the belt routing to see if a shorter belt could be used with the missing AIR pump pulley.
The AIR passages have check valves so no problem there.
The EGR is separate from the AIR system. Here you can block off the EGR tube holes, run a line from the EGR command line to the EGR Temp sensor line, with a diode inserted to fool the ECM should it call for EGR. If you run a 160 deg T-stat the ECM should never call for EGR during highway crusing.
I've been thinking of eliminating both AIR & EGR from my '88. Let us know if you are able to simple eliminate the AIR pulley and use a shorter belt.
You can look at the belt routing to see if a shorter belt could be used with the missing AIR pump pulley.
The AIR passages have check valves so no problem there.
The EGR is separate from the AIR system. Here you can block off the EGR tube holes, run a line from the EGR command line to the EGR Temp sensor line, with a diode inserted to fool the ECM should it call for EGR. If you run a 160 deg T-stat the ECM should never call for EGR during highway crusing.
I've been thinking of eliminating both AIR & EGR from my '88. Let us know if you are able to simple eliminate the AIR pulley and use a shorter belt.
Intermediate
Joined: Jan 2020
Posts: 27
Likes: 0
Air pump
..WWI have been looking in to the air pump and what it actually does. I am thinking of putting a turbo on my 88' 35 anniversary addition. Can I put the turbo in place if the air pump?
Looking at the comments it doesn't seem reasonable to discard the air pump. You will gain nothing really in the long run. I thought the air pump was used to push more air in to the throttle body
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
I have been looking in to the air pump and what it actually does. I am thinking of putting a turbo on my 88' 35 anniversary addition. Can I put the turbo in place if the air pump?
Looking at the comments it doesn't seem reasonable to discard the air pump. You will gain nothing really in the long run.
I thought the air pump was used to push more air in to the throttle body
Looking at the comments it doesn't seem reasonable to discard the air pump. You will gain nothing really in the long run.
I thought the air pump was used to push more air in to the throttle body
I beg to differ. You gain easier access to the motor without running into stuff especially if you have to take things out. You don't have the AIR tubes going into the headers to contend with.
It is an air pump since it pumps air. Actually, many refer to it as an AIR pump as in Air Injection Reaction. It's job is to push air into the exhaust manifold when it is colder to aid in conversion process and when it gets to light off temp for the cat, it diverts air into the cat. It's an emissions thing.
Intermediate
Joined: Jan 2020
Posts: 27
Likes: 0
If you can route it, more power to you.
I beg to differ. You gain easier access to the motor without running into stuff especially if you have to take things out. You don't have the AIR tubes going into the headers to contend with.
It is an air pump since it pumps air. Actually, many refer to it as an AIR pump as in Air Injection Reaction. It's job is to push air into the exhaust manifold when it is colder to aid in conversion process and when it gets to light off temp for the cat, it diverts air into the cat. It's an emissions thing.
I beg to differ. You gain easier access to the motor without running into stuff especially if you have to take things out. You don't have the AIR tubes going into the headers to contend with.
It is an air pump since it pumps air. Actually, many refer to it as an AIR pump as in Air Injection Reaction. It's job is to push air into the exhaust manifold when it is colder to aid in conversion process and when it gets to light off temp for the cat, it diverts air into the cat. It's an emissions thing.
Thank you!
Pro
Joined: Oct 2013
Posts: 627
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From: Denver CO
Advanced
Joined: Feb 2004
Posts: 75
Likes: 0
From: ATTLEBORO MA
loud is good
Drifting
Joined: Jul 2015
Posts: 1,270
Likes: 239
From: Sun City West, AZ
After a recent upper rebuild I've been thinking more and more about deleting the AIR pump.
I've been doing research about it and was wondering what you guys think would be the best approach to doing this project. Instead of getting a smog pump delete pulley could I run a smaller belt? I have access to all shapes and sizes of belts because I work at an Advance Auto. Plugging the vacuum ports and EGR? So on so forth.
I've been thinking of gutting the air pump itself and just using it as the pulley delete. 130 dollars for the delete kit is a little ridiculous. Down here in Florida we don't have any sort of emissions testing so I don't have anything to worry about. My water pump is a new aluminum so I don't want to purchase a reverse flow pump if I don't have to.
I've been doing research about it and was wondering what you guys think would be the best approach to doing this project. Instead of getting a smog pump delete pulley could I run a smaller belt? I have access to all shapes and sizes of belts because I work at an Advance Auto. Plugging the vacuum ports and EGR? So on so forth.
I've been thinking of gutting the air pump itself and just using it as the pulley delete. 130 dollars for the delete kit is a little ridiculous. Down here in Florida we don't have any sort of emissions testing so I don't have anything to worry about. My water pump is a new aluminum so I don't want to purchase a reverse flow pump if I don't have to.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Would it route right? I could have sworn that when we tried it, there was an issue which necessitated the pulley? I would love to do without the pulley but I would think (based on memory a lifetime ago) that we had an issue with it running in stock form less the pulley.
Drifting
Joined: Jul 2015
Posts: 1,270
Likes: 239
From: Sun City West, AZ
Attached is a picture of my Street Prepared L98 Engine I ran years ago before I went CAM in 2016. It shows the idler pulley in place of the smog pump. Sorry for the confusion and I blame it on old age.
