1991 3F-E De-Smog Performed (1 Viewer)

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Roger that
 
View attachment 1619119 Turns out after desmogging my rig it wasn’t enough. I overheated it attempting to keep 65 mph with a full rig going camping with the family and blew a radiator and head gasket. It was 100% my fault because I had advanced the timing and did can’t help the predet in time. But with a new head and all kinds of new parts it sounds and runs much better. Just need to replace my cats and she is as good as new! Not to mention with all that smog stuff gone I finally installed my dual battery kit.

out curiosity how much was the head gasket job....was it DIY or did you have a shop to do this,
....thanks
 
So, I read through all the pages in this thread. This is my very general take away:

- the mod can be done with or without replacing the belt and will not harm the engine.

- if you can do it, it is better to take everything away.

- the mod mainly makes the truck run smoother, it adds some noticeable torque, but not much power, if any.

- the mod might help your mpg, but most people see no change.

- some Cali trucks show code 71 (i think), but you can short the EGR to avoid it.

Did I get something wrong?
 
Nope you are right on the money. My main reason for doing it was to one get rid of a faulty system. Two make room for my dial battery kit and three to troubleshoot my lack of power issues.
 
So, I read through all the pages in this thread. This is my very general take away:

- the mod can be done with or without replacing the belt and will not harm the engine.

- if you can do it, it is better to take everything away.

- the mod mainly makes the truck run smoother, it adds some noticeable torque, but not much power, if any.

- the mod might help your mpg, but most people see no change.

- some Cali trucks show code 71 (i think), but you can short the EGR to avoid it.
I disabled my entire system. It runs way smoother, I feel I have better response, tad bit more power and better mpg. My theory is: Depending on how well your egr system is working in the first place and to what extent you remove it (just the block off plate vs. complete removal including the belt) will depend on what results you end up with.

I was happy with how well it was running and I could get up to 80mph on the interstate with 33" tires. But I didn't see a big enough increase in MPG and that has been a deal breaker for me. I live in Maine and gas stations in certain parts of the state are far and few between. I bought this rig as an "expedition" kind of vehicle and if I can't get from point A to point B then what is the sense? I just came upon an incredible deal on a low mile, aluminum 5.3 LS, 4L60e Trans, Marks Adapter and TCase. I will be doing a 3FE delete this spring. Let me know if anyone is looking for a 3FE in good condition.
 
One thing I learned is that may be able to cap the TB vac outlets and effectively disable the EGR. At least thats what I think I learned. Im chasing a high idle and it seems to be vac related, but damn if I cant find the leak, if it does exist. So in theory, I can eliminate a helluva lot of unnecessary vac, if this is correct. So Im thinking it would allow me to concentrate on a smaller area...
 
One thing I learned is that may be able to cap the TB vac outlets and effectively disable the EGR. At least thats what I think I learned. Im chasing a high idle and it seems to be vac related, but damn if I cant find the leak, if it does exist. So in theory, I can eliminate a helluva lot of unnecessary vac, if this is correct. So Im thinking it would allow me to concentrate on a smaller area...
That sounds right as long as that is the only vac line feeding the egr system.
 
That sounds right as long as that is the only vac line feeding the egr system.
Oh yeah good point. But if Im not mistaken that feeds a considerable amount of it. Will need to look it all over. I need to get these hoses straight because I AM SICK OF VAC. Sorry mild hijack
 
Hook up a vacuum gauge and tell me what you vacuum is at idle. You should be between 18 to 21. I doubt your high idle issue is because of a vacuum leak. Sounds like a tps issue.
 
Hook up a vacuum gauge and tell me what you vacuum is at idle. You should be between 18 to 21. I doubt your high idle issue is because of a vacuum leak. Sounds like a tps issue.
Will do. Thanks. Still havent got my radiator back in but Ill do this right after. Where should I take the reading at the booster? Thanks again for real.
 
You can take it from the passenger side off of the intake tube. I use the larger of the three lines.
 
I still have mine, but would rather vent directly to the intake to clean up the bay some more.
 
anyone tried this on a duel fuel lpg mixer type and does the running cooler air affect the lpg also a few yrs ago when chasing a vacuum air leak i noticed my egr vacuum modulator the thing in post #1 with the red sticker on the top was cracked on the Q port i had a spare in the shed from a old 4runner i had left over after i desmogged that so just chucked that in would this be the same egr vacuum modulator type and would useing one from a 4runner make a difference ( a mixer lpg system has hoses coming in and out of the mixer are water lines to warm the LPG to a vapour before it is fed into the air intake before the butterfly )
 
Great discussion on this thread! I am going to get this done asap. MUD does it again!
 
I still have mine, but would rather vent directly to the intake to clean up the bay some more.

Has anyone done this? Is this saying to just run the line that normally goes into the canister from the tank, running it directly to the intake? I'm rebuilding my 3FE (going in a 40) desmogged, but for now have been planning to keep the charcoal canister as I thought it was still necessary/safer. But it would be nice to have that area opened up.
 
Has anyone done this? Is this saying to just run the line that normally goes into the canister from the tank, running it directly to the intake? I'm rebuilding my 3FE (going in a 40) desmogged, but for now have been planning to keep the charcoal canister as I thought it was still necessary/safer. But it would be nice to have that area opened up.
Mine is now plugged completely (in theory with pressure/vacuum in the gas tank but haven't noticed anything so likely the gas cap has a leak) and no ill effects with regard to smells or performance.

The "Canada" spec 22R emissions system had the tank venting to the carburetor intake so it's not a completely insane concept.
 
In theory this seems like it would work. I think the steps would be very important to prevent VOC vapor from building up in the intake prior to starting. If there is too much vapor there could be a detonation during start. If I get board in a few years after all the other mods are done on my list then Ill tackle it. It will probably be solved by then.

In a roll over or steep hill decent there could be real problems.
 
My charcoal canister is bad. Was having bad tank pressure issues. I switch the hoses on the canister (essentially just venting to atmosphere I think) and it fixed the problem. So been running like that, but considering options.
 

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