The "experts" seem to think that removing the EGR will increase combustion temps. In theory this makes the engine run hotter, and in theory you should get slightly worse gas mileage. But I don't think that there is hard data showing that this is actually the case. I think that in practice, if there is a difference, you won't notice it. Like Pumpkinyota touched on, a malfunctioning EGR (or any part of the emissions system, really) will have a much more noticeable and negative effect on your truck's performance.

I think the fact that all vehicles now have EGR says something. When it's functioning properly, it does help. But they're just so prone to clogging...if you don't need one for emissions testing, or you aren't one of those people who just wants the truck to run as clean as possible the way Toyota made it...then you're probably better off without the EGR.

Off the top of my head I don't see why removing all this stuff would effect off camber driving..

I know I dont have that massive belt driven smog pump on mine ill have to check for the egr. I do have a few hoses on the pass. side fender but nothing like that pic shows.

What if i don't have this valve? I have air injection but the valve looks completely different; it looks more like a rectangular box.

That would be a reed valve. The one shown in the picture is a PAIR valve. For the purpose of this discussion, they are functionally similar enough to be treated as the same, they have the same basic purpose. The main purpose of the pics of the PAIR valve are to show you the physical location, and the location of the mounting hardware, which should be the same for either a reed valve or a pair valve.

Very nice Pumpkinyota, This was a real nugget of info!! Nice work keep it up!!

thank you very much. this was much needed.

Glad it's helpful! I will have more info up on the carbeuration side of things soon, hopefully later on tonight.

when you're done, i'm all over this. I got vacuum leaks everywhere.

So, I am new to the 83' yota and have just a little question for this thread.

I still have a EGR valve on the truck but I only have one belt. Mine has an air injected manifold, but it is removed and one of the holes is open.

Should I stop running the truck until I get it closed up?

I have access to another 22r with any engine parts.

Should I close up the hole, or should I put the original stuff back
on?

Attachment 185740

WELLLLLLLLLLLL........

I can't legally answer that question completely. Federal law says that you have to have an EGR valve installed and working if you want to operate on the highway.

That being said, unless you are somewhere where smog restrictions are highly enforced, it is unlikely that anything bad would happen, if, hypothetically, you de-smogged the truck. About the worst that would happen is that you would get a fix-it ticket if you pissed off a cop real good.

Now, also hypothetically, from an off-road only standpoint, an EGR valve is just another complicated piece of equipment to break and cause you problems. In this case, from a performance and expense standpoint, you should make sure both of those Air Injection ports on the exhaust manifold are blocked off, and the EGR will be non-functional.

Have you noticed a MASSIVE exhaust leak? Because that is what you should have with one of those ports open...

At Long Last!
 

Thread continues now:

To Recap, so far we have:

Removed EGR valve

Removed Smog Pump

Removed PAIR or REED valve

Removed Vacuum Manifold

Removed Air Injection Manifold

Blocked off Air Injection ports



Our next step is to block off the holes where the EGR used to live. Hopefully you have already either ordered and recieved block plates from here:

http://www.lceperformance.com/Block-Plates-s/1447.htm

EDIT - LINK UPDATED to correct broken link.

OR, if you are motivated, and have the tools, you can make your own block plates by tracing the outline of the EGR and EGR output tube onto some 1/8" steel plate, and cutting them out.


Here are what this will look like when done:

EGR block plate at the head:
Attachment 185724

EGR block plate at the Intake:
Attachment 185725

Attachment 185726

By exhaust leak do you mean a fluid?

There are no fluid leaks what so ever from the truck. I thought that was great from the beginning.

So running it now is not going to hurt the truck? If I run it without doing either will the engine be injured?

No, by exhaust leak, I mean a leak of exhaust. As in, clouds of exhaust billowing out of the open port in your exhaust manifold.

The engine probably won't be injured, although with an exhaust leak that size, you may introduce too much heat into your engine compartment, causing higher than average temp.

The easiest thing to do is just to block that Air Injection port. You can fab up a few plates yourself, or buy a kit from LCE for like 20$ shipped.

I will stop being that guy who messes with the thread.

I am just realizing that my truck has been about 1/2 de-smogged. I look forward to seeing the full process.

Thanks so much for the thread.

And, YES. there is an extreme exhaust leak!

No prob, the whole point of this thread is to help out, ask all the questions you want. Once this is mature, I will probably roll it into a tech writeup, and clean it up anyways.

Actually, your truck has no real functioning smog equipment anymore. Finishing the rest of this will probably make it run better and cleaner...

There would almost have to be an extreme exhaust leak. That Air Injection port on the exhaust manifold is just a port straight into the manifold, you are basically venting exhaust straight out of it with no obstruction.

So why would these two hoses be blocked? you still have those going somewhere.

Also, in the state shown below, do you feel like the carb system might have something to do with my stalling problem? It basically acted as if it was running out of gas. the thread is "83 Pickup Idle and Stall Problem."

Those springs on the throttle really bother me and I don't understand why they were put there by the previous owner.

I think I will prob keep following the thread and consider doing this, but will the fact that I am missing those tubes hurt?

Attachment 185741

Now, we are finally on to vacuum!

Thanks to Blue Bass Design for putting this info online.

Here are the important bits:

AAP - Copied verbatim from the Blue Bass site:

"All the AAP does is squirt a little extra fuel into the mixture when the engine is cold. It has no effect on the engine when warm - even when not working properly. The AAP is vacuum operated - when vacuum is applied the diaphragm opens which then adds a little extra fuel. The vacuum is applied by the BVSV which is screwed into a water jacket on the head. This senses the temperature of the coolant and applies or does not apply vacuum to the AAP."

Attachment 185727

BVSV - The BVSV is a vacuum switch that is controlled by engine temp. Think of it like the thermostat in your house: when the temperature gets to a certain point, the switch opens or closes. In the case of the BVSV, it is open by default, and closes when the engine temp warms up. Vacuum is applied to one side of the BVSV at all times, and the BVSV applies vacuum to the AAP and/or Choke Opener diaphragm when the engine is cold, allowing these to operate. Once the engine warms up, the BVSV closes, disabling the AAP and choke opener diaphragm.

BVSV Pics:
Attachment 185728

Attachment 185729


Choke Opener Diaphragm -
Again, pics and text copied verbatim from Blue Bass Design...

"This diaphragm slowly disengages the fast idle cam which in turn opens the passenger side choke plate. The choke opener, like the AAP, is also controlled by vacum from the BVSV. This diaphragm is not necessary as you can acomplish the same exact thing by punching the gas pedal when you wish to disengaged the fast idle cam."

Attachment 185730


High Altitude Compensator -
Some of these trucks have a High Altitude Compensator installed, although yours might not. Here is what it looks like:

Attachment 185731

Attachment 185732


Distributor Vacuum Advance -
This changes the distributor timing curve based on the RPM of the engine. We could spend a LOT of time discussing the reasons behind this, but as this is a de-smog thread, not a basic mechanical thread, we won't give much detail here.

Attachment 185733


Charcoal Canister -

Verbatim from Blue Bass:
"The charcoal canister(s)'s job is to vent the gas tank. Basically the worst that will happen if they are clogged is when your tank gets near empty and you undo the gas cap, you will hear a whoosh of air go into the tank. This is because a vacuum is created in the tank as gas leaves and no air can enter through the canister due to it being clogged. You can usually blow the canister(s) out with air to unclog them."

Attachment 185734

The vacuum ports that you have circled there are for the high altitude compensator. As you don't have one installed, having them blocked off is correct.


The spring shown is a redneck'ed in replacement for the throttle return spring. It probably isn't hurting anything, but you can get a much better spring at your local hardware store for a couple bucks.

You can add or remove many of these features and functionalities, depending on how you operate your vehicle, how simple you want it to be, how well you want it to cold-start, etc.

Here is the base minimum:

Remove all vacuum lines from your carb. Install the following:

Distributor vacuum advance:
Attachment 185735

Port 1, in yellow, to port 1, in yellow, in the following pic. The same for port 2, in green. Keep in mind, these pics are to show you the location of the vacuum ports, mine is set up to include the HAC, so the actual vacuum lines between will take a slightly different path.

Attachment 185736


Install a vacuum line from the carb to the charcoal cannister (#1, in yellow). Make sure that the fuel return line is installed (#2, in green).

Attachment 185737

Cap every other vacuum line off, and you can roll just like that.



And, now I am having connection issues with YotaTech, so we will have to continue this later. Coming soon though, my attempt at a well balanced setup.

Great post!

I just checked under my hood, I still have an EGR valve inplace.

My question, if I remove the valve and the tube, then make a blocking plate out of something thin, like a pop can, then put everything back together with the blocking shim in place, will this give me the same result as if I removed everything from the truck?

Thanks

Yes, as long as you get a good seal. On mine, for the time being, I just plugged all the vacuum hoses going to the egr and left it all in place.

Wow fantastic write up so far:bump:

quick question if the carbon canisters only job is to vent the gas tank is it really needed?
when i bought my truck the canister was mounted but there were no hoses attached... so I just pitched it... now I'm wondering if I need to go dumpster diving:think:

Hmmmm... Well, as stated at the beginning of the thread, I can't legally advise you on ways that you can circumvent a local smog check. That being the case, I can tell you that if you are de-smogging for offroad use, and you are too cheap to buy or fab a new plate, this would probably work fine.

That's all it is for. :)


EDIT: It is probably OK to roll without, you will hear a hiss every time you fuel up. The carbon canister also does some vapor recovery, which can come in handy, especially if you are putting the truck at any severe angles offroad. A lot of people mod the Aisin carb, and add a second charcoal canister, and put an overflow vent on one of the bowls in the carb. If you are at all interested in this mod, let me know and I'll toss up a link to a post explaining this in depth.

Hey guy's I'm new to yotatech and I'm happy to see you guy's have started this thread. Real quick info about emissions. I have a buddy who is from Mexico and we got to talking about Toyota's and he was saying that they do not like anything past 3rd gen yotas. He says they are crap and they don't last as long as the older ones. Anyways he was telling me his grandfather has an 81 4x4 flat bed ranch truck that he bought brand new and still has it to this day with over 400,000 miles! The key to that he said was no emissions. Just thought I would share.

I am in the middle of rebuilding my carb and de smogging my 83 now. I would be interested in reading a little more info on this Aisan mod if you have the link.

Alright, here is the link. There are all sorts of good-idea mods in this thread.

Pirate thread on Carb Tuning:
http://www.pirate4x4.com/forum/showthread.php?t=249626

Good Luck!

EDIT: Here's another pirate thread on Carb tuning, more specific to this mod:

http://www.pirate4x4.com/forum/showt...highlight=carb

I too have de somged my engine. It is a 22r. My engine is heavily modified to the point of a 4bbl carb, cam and header. My question is how do you adjust your air conditioner compressor belt? On my engine the smog pump has the adjustment for the ac compressor.

Can you throw up a pic of the front of your motor for me? You probably need to get a smaller belt.

Also, why a 4bbl carb? the stock Aisin or a weber puts more than enough gas down that intake for any power requirement that a 22r will ever have, you are probably gas-washing the cylinders. Get ready for a re-ring...

And to all following: sorry for the delay in finishing this how-to, my life has gone CRAZY in the last couple of months. I promise completion to this thread eventually...

I have a wide band air fuel ratio gauge, that would argue with the washing the cylinders. When the secondaries open she breaths fine and burns well. I am in the build process of the truck I drove it enough to make sure she was running clean.
Now it is parked in the garage waiting on air lockers, air system, diff gears, 4 wheel disk brakes, a new cross member with a integral drive line parking brake, a flat bed, new 5 inch lift, cross over steering, dual trans cases, dual 8000 lbs winches, shock hoops, interior, rust repair, paint, custom bumper and rock sliders. Most of the parts are in the back of the truck, I need to get it back on its tires. I have the axles out from under it for welding and the reassembly, and the lockers are back ordered.
I have owned the truck since new, I bought it in Pasadena Ca, but now live in Wichita KS. The winter salt is tough on the old girl and she needs to be patched, painted and undercoated. The engine compartment will be dressed after I install a bigger new/used booster and master cylinder.
By the way I once held a smog license in California. I left auto repair and have been repairing heavy equipment for about 20 years. Diff rebuild, metal fabricating and engine rebuild are part of what I do for a living and are still easy to transfer into the old truck.

This week I am reworking the throttle cable. I was unhappy with the way I had it before. I am also wiring in the electric choke.

Attachment 185716

This is a pic of the only block off plate left on the engine. I built this and others but did not use any when the 4 bbl manifold and header were installed.

Attachment 185717

I am still using the smog pump as a pulley. It is no longer a pump as it failed a few years ago and I gutted it. The bearings were still good so what the heck.

Attachment 185718

She ain't perdy but she scoots along pretty good.

Alright, so this one made e think a little. My truck has no AC, thus no compressor for me, and no belt, and no problem.

For you, as a fabricator, you might consider building a custom tensioner rig using the front of the smog pump bracket and an extra fan belt tensioner from a pick & pull. I will pop my hood when I get home and see how feasible this is...

I thought Toyota had a idler pulley for that area. I am going to look in that direction.

vacuum
 

Pumpmkin, great post! could you please post up how you ran your vacuum hoses to incorporate the hac please, thanks!

I believe the 22RE did not come equipped with a smog pump (89-95 anyway) and that is where i'd go to get a stock idler pulley. But my A/c is broken so it's not high priority right now.

just saying thanks for the write up. i just did this to my truck and it works great!

Now I feel mildly jerky, I have gotten all caught up in my secular work, and haven't completed this writeup =(...

I will try and get this up tomorrow for you, sorry for the delay.

Really glad this was helpful to you! When I was doing it, i couldn't find a good writeup on de-smogging specifically anywhere, and I had to figure it out from basic principles. Fortunately, I was able to dig up info from places like Blue Bass Design and YT, I could not have figured anything out without the wealth of info available from these sites.

Ever getting this wrapped up?

i have three aisin carbs, i couldnt get any of them to run right on my 22r, i tried this and i found one that runs "better" but still not quite right.

I did this on my RE also

Thanks for all the info it was appreciated!

if you ever get a chance you should put after pics up of block off plates and vaccum lines!:bounce: