1991 3F-E De-Smog Performed

[elprup87]

Update:

I went on a 400+ mile round-trip last weekend and mileage one way was about 18 mpg, but was mostly downhill and with a 20-30 mph tailwind for most of the trip. Mileage coming back, mostly uphill with a 20-30 mph crosswind or headwind and the AC on about half the trip was 14.5 mpg. DEFINITELY an improvement!

For the last couple of years, the best mpg I've gotten was about 14.5 - no AC, downhill, tailwind, etc all working in my favor.

Again, I didn't mess with the smog pump, but only did the vacuum hose mod.

Pretty close to my results. I performed this mod several months ago, but only recently made a nice long trip for the numbers. Sadly today my 310 miles were all met with wind (20-30mph crosswinds). Average cruising speed of 68-ish and upon fillup placed 19.2 gallons in the tank. Nice 16 mpg. All stock drivetrain, no flares or front bumper (sadly not yet). Figured the flat nose of no front bumper would hurt my milage.

 

[savageX]

For those of us who live in an emissions-controlled area, the BB method is more stealthy. And you only change out the belt for the longer one once a year.

why not just place 2 bb in the two main vacume lines to keep the stealthyness there instead of unpluging and caping them off.

 

[lt1fire]

Done.... I will be doing about 1000 miles to the outer banks and back next week so i'll keep a tab on my mpg numbers.

 

[lordbater]

Groovy, I've put the belt back on and haven't seen much if any fuel change. I did it for the state inspection. I compared the numbers from last years inspection before the desmog BBs, and the numbers were much better desmogged, I'll post them up if I can find them...

a

 

[lyrikz]

Good thread. Just found it.

When you guys are doing this, what do you do with this pump?

You removing that??? How do you block it off? My LC is a 1993. I have no emissions where i live and its only driven to the mud. Cats are gone also.

 

[Eicca]

The engine in the 1993 is COMPLETELY different from those in the 1991-92. This more than likely won't work for your rig.

 

[cool breeze]

Good thread. Just found it.

When you guys are doing this, what do you do with this pump?

You removing that??? How do you block it off? My LC is a 1993. I have no emissions where i live and its only driven to the mud. Cats are gone also.

To remove the PAIR system is very straight forward once you get to turning wrenches. Use the gaskets on the tubing coming off the exhaust manifold to make some block off plates, I used some galvanized 20ga sheet metal i had laying around. Only thing i haven't got around to is finding a nice rubber nipple to block the large hole coming off the air box

Results i have noticed:
not much mpg increase,
slightly better throttle response,
no more white puff during cold startups. This could be from also from AutoRx treatment nut when i pulled the piece off there was about 2-3oz of water in the plastic box.

Hope that helps

 

[sbisig]

This morning I installed the BBs in my 92 and then made a 135 mile round trip up I-5 through Seattle and back - average speed 60 mph with about 15 miles of that on city streets. I'm still running the smog pump belt.

On this initial run, I got 13 mpg. My recent average has been 10-12 mpg. Not a huge improvement, but not bad considering the ARB roof rack, stock gears, mud tires, bull bar and winch.

The one thing I noticed on the initial drive was the ability to pull more hills without downshifting as frequently. This alone is worth the mod for me.

I can't wait to continue with the rest of the de-smog process.

 

[alex4640]

I have not done the BB mod yet, but I plan to. What I have done is remove the EGR code from my 3FE permanently. I simply stripped some of the insulator from both EGR Temperature Sensor (EGRTS) wires about 2 inches from the sensor and twisted them together. I then wrapped the whole thing in electrical tape to hide the mod and no more EGR codes. I have also passed emissions tests in Texas for 4 years with this mod. I'm really not sure why this works but it does. Perhaps some of the Toyota experts can research why. From what I can gather the 71 code comes from the (EGRST) not giving what the computer wants to see.

 

[Big C]

im pretty new to this whole landcruiser thing and i was wondering what the point of desmoging is? I really dont kno much about it.

Thanks

 

[Big C]

never mind on the last post. haha. Should i put a BB on both ends of the line or just one?

 

[elprup87]

I have not done the BB mod yet, but I plan to. What I have done is remove the EGR code from my 3FE permanently. I simply stripped some of the insulator from both EGR Temperature Sensor (EGRTS) wires about 2 inches from the sensor and twisted them together. I then wrapped the whole thing in electrical tape to hide the mod and no more EGR codes. I have also passed emissions tests in Texas for 4 years with this mod. I'm really not sure why this works but it does. Perhaps some of the Toyota experts can research why. From what I can gather the 71 code comes from the (EGRST) not giving what the computer wants to see.

Simply jumper the loop? Sounds simple. I have used the BB method, but since I am taking everything apart for the headjob I plan on removing the EGR system. I already have the air injection manifold plugs on order from Toyota. Just need to cap off the EGR area on the intake. Mine was pretty messy.

 

[Godwin]

Only thing i haven't got around to is finding a nice rubber nipple to block the large hole coming off the air box

Can't tell from the pic but is there a short tube coming off the box? If so, track down some crutch tips, you may be able to find one that fits close enough to block the hole. The crutch tip may not be an exact fit but silicone can be used to fill the gap and keep the crutch tip on. This is the approach I used on a 2F air box and it's worked well.

 

[Eicca]

I found something interesting...

My gain in power came not from disabling the EGR, but from capping just two of the lines that attach at the fender. Capping those two also smoothed out my idle and raised it a touch. I'm going to mess around with it a bit more and post results but that's something you can think about

 

[arbolmano]

Greetings
I'm a new person to this site but not to de-smogging. Did time as a smog tech here in California. One word of caution in disabling the air pump. They will sieze up on you when not turned from time to time and are pricey if you need to pass inspection.

 

[elprup87]

I found something interesting...

My gain in power came not from disabling the EGR, but from capping just two of the lines that attach at the fender. Capping those two also smoothed out my idle and raised it a touch. I'm going to mess around with it a bit more and post results but that's something you can think about

I had that effect as well. However I did appear to notice a slightly better pickup (maybe just low end umph) a little. But I did just the BB method at that time. I also noticed that my milage didnt really change that much (either way). I think my milage will change after my injector cleanings, head shaving (from warping, 13 thousandths), complete removal smog stuff. But thats another story.

 

[remac226]

Did it at lunch in 15 minutes. Made a big difference on my truck!

 

[gt4runr]

Did BB mod and 10 miles after, got a cel 71 code. Anyone figure out what's going on with that? Possible cure other than removing bb's? Thanks!

 

[Eicca]

Well I just passed emissions with the BBs in the EGR. Almost no change in numbers

 

[PabloCruise]

I just found this thread and really enjoyed reading it (my guess is you will only enjoy thread if you enjoy messing with the 3FE.

I wanted to include some 3FE vacuum schematics in order to help everyone understand what lines feed what systems.

NOTE, I found these schematics when researching the 3FE that came out of an early FJ-62. I am not sure what differences btwn the 62 3FE vs. the 3FE for 80 series!

I color coded my schematic by system - it helped me keep track of the different circuits (also shows mods for putting 3FE in my FJ-55):

From here: https://forum.ih8mud.com/60-series-wagons/272486-3fe-vacuum-schematic-needed-88-62-a.html