So I read the forum and I'm pretty sure I could, and I have a good reason....

Could I leave all my emissions equipment on, with everything plugged with homemade plugs (vacuum line with a screw/black rtv) and just run a weber ? Im not required to smog my vehicle yet, but I'm a little Leary about the next couple of years... There's been a few bills introduced, just not passed yet. Forgive me if it sounds silly. I just am so tired of trying to tune my Asian when more then half my Vaccum devices don't work according to the testing I did with an old manual.

I tried plugging everything with the Asian carb and it ran worse. So didn't know if I ran the weber kit a just left all my stuff plugged so "it was still there at least) even though it's ugly and doesn't work...

 

Lceperformance.com sells an In-house fuel pressure regulator with gauge kit, that is set for the fuel line size on 20/22r(e)s. Not sure if it's cheaper than Holley and guage separately. but you don't need to call/drive around to parts stores for fittings etc

 

It is certainly possible to just plug everything to desmog; however, I have to caution you that you want to use silicone plugs in lieu of rubber. The rubber plugs have the tendency to crack over a short period of time leaving you in a spiraling nightmare of vacuum leaks. The Aisin carb is rather difficult to tune to begin with (by far one of the more difficult carbs I have even tuned) plus it is also somewhat dependent on emissions so desmogging doesn't help the process either. It can certainly be done, but it takes some patience and figuring out. Be very diligent in plugging the emissions so as to not develop any vacuum leaks. Webers are definitely more user friendly so I would go that route if you can.

I too know what it is like to live in one of "those" states. At the earliest opportunity, I'm moving my family out of Maryland and heading 10 minutes up the road to Delaware. I'm sick of the ridiculous liberal politics and policies driven by the metropolitan portions of the State.

 

Thanks for the information. Yes I'm stuck in Natzifornia but Idaho will be home again soon. Once I sell my Asian carb, hopefully soon I'll post results of my new weber and redneck desmog

 

Where are you guys finding the intake manifold plugs for the big one at the center, and then the three on the top near the water port? I tried the hardware store but they didn't have metric brass fittings.

For now I just put back in the plugs that had wires coming out but they're ugly. And for the middle one I just brazed it shut from the threaded side.

I'll get some pictures of the completed job up when I'm done. Waiting on a new intake manifold gasket to show up. Had a horrible time with one broken off bolt stuck in the head, made the mistake of trying to extract it rather than drilling out and re-tapping. So I spent hours trying to get the ultra hard extractor out of there and then had to size up and helicoil...lesson learned, never use those stupid extractors.

 

The plugs are what I believe is called British threads with. 28 threads per in and pipe is 29 per in or its reversed. Lceperformance makes a plug kit you could call and see if they can make one or if they even sell one. They're kinda the only ones making 99% of parts needed for desmog

 

Another succesful desmog thanks to this thread! Look at all this junk you get to nix from under your hood. Feels great.

 

I'm giving this a shot with my Aisan carb. So far I've removed all the VSV's, evap canisters and the PAIR pump/hoses. The EGR is untouched and the PAIR valve box is still there.

I have a question though. It looks like the idle advance on the distributor went to a vacuum switch on the passenger fender (brass color, one wire, one hose.) So far I have just left it open, but plugging it doesn't change anything. Being connected to just a switch means there was no way for vacuum to hit that port, so what does it even do? I'm guessing it was an input to the computer. Of course Toyota had it there for a reason, anyone know what it actually does?

 

The port on the vacuum advance towards the front of your truck/ closest to your radiator needs to be plugged into a port on your carb that has vacuum- what that port does is advance the timing when accelerator is pushed for power/high end.

The port closest to the rear of your truck (towards the firewall) retards the timing when vacuum is applied. It's to help lower emissions.

Lce says plug the rear vacuum advance port but I would plug it in one of the ports with constant vacuum on the manifold. I used one of the 3 ports off that big piece in the center of the manifold below the carb and I plugged everything else.

 

I did some research, and that port actually does have vacuum. There's a T somewhere inside the metal hardlines that I couldn't see. It's not just a vacuum switch like I thought, though that is certainly a part of it. So, me leaving it unplugged is actually causing a vacuum leak. Neat! I should be able to just plug the hardline and have the same vacuum ref. as before.

Anyone know what the vacuum switch is actually for? Prolly just emissions garbage?

 

Every single vacuum line on the 20/22rs are for emissions sake.
Plug everything except what's needed for the two hoses off the distributor, put a filter kit on the front valve cover vent and keep a pcv valve routed to the vacuum port.

 

you don't need a carb or fuel filters? Awesome

 

Oh, I have an issue now. The engine seems to stumble when I'm just barely on the throttle and up over 2000 RPM. Idle is great, and throttle more than ~30% works great. It's mostly when I'm slowing down or on a downward slope on the highway, so I'm barely touching the gas. Doesn't seem to do it when I'm all the way off the gas. Any ideas? I can't really spray carb cleaner around my hoses when I'm doing 60 on the highway, but I don't think it's a vacuum leak.

I've plugged the lines for:
MC valve
HAI
Evap
PAIR
Vacuum Switch

The PAIR box is still on there, but I've removed all the hoses. EGR is still there. Basically I took off everything that didn't require a block plate.

 

It's a hybrid...

If you're using the Aisin carb then it is likely a tuning issue that needs to be resolved (assuming no vacuum leaks). Those Aisin carbs are pretty much the most difficult carbs I have ever worked on! I would just mark down your current baseline and start making small individual tweaks. Run it for a little bit and see if it gets better or worse. Can't promise that you'll find the solution, but you may be able to isolate the problem a little easier.

 

I'm starting to kick myself as the truck was running great before I went to messing with it.

I should also add that when downshifting and coasting the exhaust pops a good bit, but this was happening before I removed anything.

Is it possible the fuel cut solenoid or EGR are acting up? I still haven't been able to figure out what the "vacuum switch" actually does as far as emissions control.

 

The valve thatnis between the air pump and that hard metal hose (air injection tube) that goes to your manifold has an anti back fire valve. Sounds like that is failing. I blocked my air injection ports to by pass it as a protective measure.

 

Does the PAIR valve connect to the intake manifold at all? If not, I wouldn't think it could cause my stumble-under light load issue, worst case would be an exhaust leak. I do suspect one of the remaining emissions systems is causing this though. I have a car with a sticky EGR valve, and it bucks the same way sometimes. Is there a hose I can pull that kills the EGR without blocking everything off? I'm still at the stage where I can go back and put all the crap back on, so I'd like to make sure it's fixed before I go any further.

It's a 88 2wd federal emissions, which I think means PAIR and not reed, but I'm not sure. There's no little resonator hanging off the air cleaner.

 

I'm almost certain I have it figured out. It was the "vacuum switch" after all. The FSM doesn't come out and say what exactly it does, but does detail a test (page EC-65 in the 1987 FSM) that involves pinching off the hose to it and seeing if the engine sputters between 1800 and 3000 RPM. The idea I think is that if you let off the gas all the way, the idle jet is blocked so no extra fuel gets wasted. Mine is still messed up, as I get a lot of exhaust popping, but that I can live with.

With the VS removed and disconnected, it cuts fuel to the idle circuit even when you are in light throttle, (light enough to be using the idle jet) this was causing my stumbling problem, and also explained why it didn't happen when I was more on the gas, since it was using the main jets by then. Some other posts on the "light load stumbling" issue suggest a failed FCS, but I haven't seen anyone suggest the VS yet. Then again, desmogging the truck is a special case.

The behavior of the circuit seems counter intuitive, since you'd think the fuel cut would be triggered by seeing vacuum on that port, while having it disconnected would be telling the computer that the throttle is not at idle. Since the emissions control computer is TTL based, however, the input will have a tendency to float to a "logical high" voltage, which based on the diagram of the switch will actually send the "idle position" signal to the computer. Thus, the truck will hit the fuel cut solenoid whenever the engine speed is high enough (2200 RPM on mine). Once again, this doesn't cause a problem if you are off the throttle or on it enough to be using the main jet.

A proper way to get around this will be to ground out that input (telling the computer you are always on the throttle), remove/disable the fuel cut, or get the Weber like OP said. I will try the first option when I have time. Until then, I'll just leave it on there.

Interesting as well, earlier I was asking about the idle advance being plumbed into the same circuit as this Vacuum Switch. Turns out they are both looking at the same thing, trying to activate only when the throttle is at idle. I guess Toyota was pretty smart when they were figuring all this out. Neat stuff.

Here's the page that explains the operation, maybe it will help someone else:





EC-64 deceleration fuel cut system

 

Subscribed! great write up!! vary through and interesting.

I will be doing this at some point, but first I got to ensure the used 22r engine I just dropped in, with all stock components, runs before removing anything...

 

Just a FYI, you'll likely have less problems sparking up that engine WITHOUT the smog emissions equipment than you would with it. Desmogging will remove several variables that could cause you issues. I rebuilt my 22R and let it sit for nearly 2 years while I restored the rest of the truck. It fired right up when I went to start it for the first time. Set the timing, adjusted the carb and I was rolling down the road in no time.