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Successful 86 Vette EGR/AIR/Emissions System Removal - For the curious.

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Successful 86 Vette EGR/AIR/Emissions System Removal - For the curious.

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Old 07-03-2010, 05:47 PM
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Aopsahl7
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Default Successful 86 Vette EGR/AIR/Emissions System Removal - For the curious.

I was not able to find a good answer to this when I was searching around before so I figure I would do a brief write up on it for the future lookers.

on the 86 and others there is the AIR system and EGR system that some argue take some performance off, but mostly just clutter up the engine bay. So I decided to take it off. The exact answer to wether or not you can pass emissions/smog testing is unclear.

The first step is to remove the AIR system hoses, switches, and relays. There are two switches/relays under the throttle body that have several hoses attached to them. You can remove that stuff and just hide away the old plugs/wires. Then for the stock manifolds, you can remove the one way valve on each side, and pickup 2 5/8's plumbing pipe caps to cap them off. As far as the air pump goes, there is a replacement pulley that is available, but it is ~$150. I just removed the AIR pump and took out the insides/fan so it just spins freely.

For the EGR system, I did not remove the EGR pipe that runs from the right manifold up to the plenum area. But I did remove all the little vaccum lines and picked up some small rubber plug caps to cap off the vacuum line holes...there are three that I capped. Then the EGR solenoid that is underneath the throttle body on the drivers side can be unplugged and removed.

Some people take a few more steps and compeltely remove the entire system, but I just wanted to clean up the engine bay and this did the job.

I did not get any SES lights or Check engine lights after the removal. THe performance gains (if any) are not noticeable.

I hope this helps for the future lookers.

Happy 4th.
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Old 07-03-2010, 05:55 PM
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Nice write up.

You are correct, not many questions get answered here much any more, I think many see it as they have answered the question too many times, or someone else will.

I have a 90' and the smog pump was on, but there was no egr or anything else, and it passed smog in WI. (I am not saying any one else's will.)
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Old 07-03-2010, 09:31 PM
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I am suprised that the egr removal threw no codes. I have been wondering about that as I am tempted to do the same thing on my 86.
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Old 07-04-2010, 05:37 AM
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i wanna do this to in my 87

but will i still pass phx az emmisions..lol
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Old 07-04-2010, 10:30 AM
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I remember reading once that the air pump took about 3 hp to drive at 7000 rpm, not even worth considering.

The only nice part about this (IMHO) is that it cleans up the engine compartment.

Great info though for all those who may ask again, and again, and again......
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Old 07-04-2010, 03:28 PM
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Originally Posted by Aopsahl7 View Post
The exact answer to wether or not you can pass emissions/smog testing is unclear.
That's because no exact answer can be given. It mainly comes down to weather or not your area or state does a visual inspection of your engine bay in the first place in addition to the analyzer test.

I've had my '86 put on a CA analyzer machine with no air system and a disabled EGR. I passed just fine and all my emission readings where well within state limits BUT failed the visual inspection because CA also looks at your engine bay for modifications to emissions components and such. Failing a visual is failing everything regardless of your analyzer readings.

So I know from first hand experience and a real test that a properly tuned C4 is still capable of meeting strict CA emission standards without AIR or EGR function. I've done it and I stood there watching the readings on the analyzer myself.

If you do have a visual inspection to undergo then you will always fail with missing AIR tubes, capped off manifolds, and tucked away AIR diverter valve connectors unless you know the guy or something. So you better either keep all that stuff in a box to reinstall before you next test or just don't bother in the first place because it still isn't going to matter if your emission numbers are within allowable limits.

By your post it sounds like Maryland doesn't do visual and only goes by your emission output (which is what I wish CA would do here). If that's the case than the answer to you is yes you can get away with it if everything else (like your main cat, your timing etc.) is in order and your emission numbers are still within legal limits like mine where, and they don't even look at your engine bay.

Last edited by 86PACER; 07-04-2010 at 03:48 PM.
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Old 09-29-2011, 12:35 PM
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Default Question / not reply // emissions

I have a 1990 L98 with a LT1 intake. No egr and mass airflow sensor. I have read that there is a kit for the emissions removal. With my setup, do I need anything seperate or different? Is there a reason to remove the smog/ air pump besides cosmetic? Thanks and Help !!!
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Old 09-29-2011, 01:06 PM
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Originally Posted by mcm95403 View Post
I remember reading once that the air pump took about 3 hp to drive at 7000 rpm, not even worth considering.

The only nice part about this (IMHO) is that it cleans up the engine compartment.

Great info though for all those who may ask again, and again, and again......
3 hp at 7000 rpm, is there a book or online to read about this?
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Old 12-14-2011, 12:31 AM
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jeff mattson
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heres a good one , id like to locate my egr on 1983 buick skylark, 2.5 cylinder tbi i found distributer cap,cruise control, they are behind the motor, i am wondering this because i am ready to do full systems test on my allen sea engine analyzer, one of steps is to disable egr,
if i dont disable egr , on this engine is it gonna throw test results off.
i replaced the plug wires and plugs. because i was having a cold start problem gota flip motor forward to change cap and rotor. slight hesitation is sometimes there with ruff idle sometimes when letting off gas coming down to stop. besides air gap on cap and rotor i think fuel filter is contributing to this problem, possible pcv valve worn? egr?, car has low miles 69k i got a part for scope vac/presssure transducer the other day, il be able to test puppy hopefully , now and maybe be able to smoke the tires, if i cure problem anybody have any ideas or work on this motor before?
thanks jeff
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Old 12-14-2011, 01:00 AM
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Originally Posted by jeff mattson View Post
heres a good one , id like to locate my egr on 1983 buick skylark, 2.5 cylinder tbi i found distributer cap,cruise control, they are behind the motor, i am wondering this because i am ready to do full systems test on my allen sea engine analyzer, one of steps is to disable egr,
if i dont disable egr , on this engine is it gonna throw test results off.
i replaced the plug wires and plugs. because i was having a cold start problem gota flip motor forward to change cap and rotor. slight hesitation is sometimes there with ruff idle sometimes when letting off gas coming down to stop. besides air gap on cap and rotor i think fuel filter is contributing to this problem, possible pcv valve worn? egr?, car has low miles 69k i got a part for scope vac/presssure transducer the other day, il be able to test puppy hopefully , now and maybe be able to smoke the tires, if i cure problem anybody have any ideas or work on this motor before?
thanks jeff
wait, what?
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Old 12-15-2011, 03:20 PM
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jeff mattson
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Originally Posted by hypntyz View Post
wait, what?
i know was just kidding about smoking tires,
if anyone has exp using the allen sea./allen smart scope
let me know.
i am new at using this machine.
i am used to using my sun machines, but they are down due to minor problems.
yes i am a mechanic.
i have many parts for old sun,.allen,bear engine analyzers. for sale at very reasonable prices. also user manuals/service manuals are available for sale, upon demand.
pm me or goto ebay seller mnnorthwoods.
if you are interested.
thanks jeff
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Old 12-16-2011, 01:17 PM
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hypntyz
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Originally Posted by jeff mattson View Post
heres a good one , id like to locate my egr on 1983 buick skylark, 2.5 cylinder tbi i found distributer cap,cruise control, they are behind the motor, i am wondering this because i am ready to do full systems test on my allen sea engine analyzer, one of steps is to disable egr,
if i dont disable egr , on this engine is it gonna throw test results off.
i replaced the plug wires and plugs. because i was having a cold start problem gota flip motor forward to change cap and rotor. slight hesitation is sometimes there with ruff idle sometimes when letting off gas coming down to stop. besides air gap on cap and rotor i think fuel filter is contributing to this problem, possible pcv valve worn? egr?, car has low miles 69k i got a part for scope vac/presssure transducer the other day, il be able to test puppy hopefully , now and maybe be able to smoke the tires, if i cure problem anybody have any ideas or work on this motor before?
thanks jeff
Originally Posted by jeff mattson View Post
i know was just kidding about smoking tires,
if anyone has exp using the allen sea./allen smart scope
let me know.
i am new at using this machine.
i am used to using my sun machines, but they are down due to minor problems.
yes i am a mechanic.
i have many parts for old sun,.allen,bear engine analyzers. for sale at very reasonable prices. also user manuals/service manuals are available for sale, upon demand.
pm me or goto ebay seller mnnorthwoods.
if you are interested.
thanks jeff
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boy was cryin and went to pic up her body

she was ded

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(dat mean he luv her moar dan 4evr.....)

SHARE IF DIS MADE U CRY
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Old 05-09-2012, 04:50 PM
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Default EGR trouble

Everyone seems to be removing the egr system and I am looking to replace mine. Cannot pass emmision testing with out it. The Nox is double the allowable limit. I am looking for parts and pics to replace to original or as close to original as possible. Wish the previous owner kept their hands off!! now I have a rather large paperweight in the garage.help please
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Old 05-09-2012, 05:09 PM
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Originally Posted by shopboy View Post
Everyone seems to be removing the egr system and I am looking to replace mine. Cannot pass emmision testing with out it. The Nox is double the allowable limit. I am looking for parts and pics to replace to original or as close to original as possible. Wish the previous owner kept their hands off!! now I have a rather large paperweight in the garage.help please
Try salvage yards. I have been getting some good stuff from Corvette nutz and corvettesalvage.com. I got a 93 with a lot of stuff missing.

For everyone else who has removed EGR, what do you do about the possibility of detonation at cruise? A PO removed all my smog stuff. I am thinking about adding it back in or getting it tuned out, but I want to understand what exactly has to be done to tune it out so I know the tuner is doing it right.
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Old 05-09-2012, 05:39 PM
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The EGR system helps to prevent your motor from detonation it also helps you get better gas mileage.Some of those lines you removed also vent your gas tank.On a scale of ten your ear can only pickup one so your engine could be detonating the other nine and you won't hear it.Your knock sensor will retard your timing.and you will lose power and mileage.
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Old 05-09-2012, 06:54 PM
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Almost two years old....
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Old 05-08-2018, 03:48 PM
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I've just seen your thread and performed the procedure, I think. I'm a disabled Vet, however, can still get around and my '86 Vette is kinda my therapy. Some stretching but alls good Herein lies the problem, runs awesome until operating temp is reached, then misfires/stumbles/power loss.I'm going to get another pair of eyes on it to see if I removed and capped everything, which I think I did. I've moved to Martinsburg, WV so as to be close to my VAMC so your not to far away. Please respond.
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Old 05-08-2018, 03:57 PM
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Default 86 Vette EGR/AIR/Emissions System Removal

I've just seen your thread and performed the procedure, I think. I'm a disabled Vet, however, can still get around and my '86 Vette is kinda my therapy. Some stretching but alls good Herein lies the problem: runs awesome until operating temp is reached, then misfires/stumbles/power loss.I'm going to get another pair of eyes on it to see if I removed and capped everything, which I think I did. I've moved to Martinsburg, WV so as to be close to my VAMC so your not to far away. Please respond.
Thanks,
K S Bledsoe
USMC (retired)
email @ [email protected]
PH (304) 350-7220
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Old 07-07-2018, 01:52 PM
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Originally Posted by steven mack View Post
The EGR system helps to prevent your motor from detonation it also helps you get better gas mileage.Some of those lines you removed also vent your gas tank.On a scale of ten your ear can only pickup one so your engine could be detonating the other nine and you won't hear it.Your knock sensor will retard your timing.and you will lose power and mileage.
...thought so... was looking for confirmation... seems like a lot of work to remove it, just to annoy your engine... why Not leave it alone... it's doing something good for your engine, it's unobtrusive, not in the way...

The Smog Pump though, what a bunch of junk. I love the environment just as anybody else that might, but... that damn thing is all over the place, must weigh a ton, altogether. Along with it's resistance, there's that whole weight/horsepower ratio, the yin and yang of auto racing, that it futzez around with . If it's not going to hurt anything, I'm going to rip it out. It's in the way of the spark plugs and boots, somewhat, and other stuff as well. Especially on the passenger side. The Plug closest to the front of the car will be a project with all that smog crap in the way. I'm getting ready to change plugs an wires and such. The previous owner left a spark plug boot loose (passenger side, 3rd from front of car, I just plucked it away from the plug) probably because he had a hard time working around the smog pump junk. I'm going to read some threads here and then maybe some YouTube, if any, and begin ripping it out. I guess I'll gut the pump, til I can get the nerve to buy the bypass pulley.
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Old 07-07-2018, 02:46 PM
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Not so much interested in added HP, more in cleaned up engine bay. Gonna have all that crap yanked this winter during storage/service at my Corvette whisperer. No smog inspections or engine-bay checks here in Illinois so no issues with all that being gone for good.
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