Lets talk 3fe Desmog. (1 Viewer)

DESMOG

  • YES

    Votes: 44 91.7%
  • NO

    Votes: 4 8.3%

  • Total voters
    48

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@62LostInMn There is a desmog guide specific to FJ62s that was posted here 3F-E Desmog. It's what I followed and it brakes up the process into a couple of segments, if you don't want to do it all at once.
 
OK - you got me Captain Obvious...;)
I suppose the only "maybe" is if the EGR is stuck partially open... We'll give it a try and see what happens.

Go back through the 60 section and you'll see almost every post related to 3FE desmog will state there's minimal to no effect on the way the motor runs. It is highly unlikely you will be able to tell a difference.
 
Yep, I didn't notice a substantial difference in base line engine performance after desmogging. I decided to desmog after the VSV leading to the air rail totally disintegrated on me.

Desmogging is a good opportunity to go through the EF chapter of the FSM and to check for intake and vacuum leaks. You're more likely to notice an improvement just by cleaning your throttle body and replacing leaky hoses.
 
My 3fe had a rough idle. When I blocked the EGR it went away via the BB's in the vacuum line. My guess is there were additional vacuum leaks.

Also my MPG increased and it ran better. But if your 3fe is well running and without issues my guess is it won't improve. But I do believe taking out the EGR will increase MPG. Putting only fresh air into the combustion cycle is better than previously burned poison. My belief.
 
Also my MPG increased and it ran better. But if your 3fe is well running and without issues my guess is it won't improve. But I do believe taking out the EGR will increase MPG. Putting only fresh air into the combustion cycle is better than previously burned poison. My belief.

You may be right, but the point of EGR is to slow the combustion process (by introducing a less combustible gas) to prevent spark knock and lower combustion temps to prevent NOX formation.

Regarding desmogging, with a totally stock engine, at least you can troubleshoot using standard procedures, without wondering if your mods are affecting engine performance. It's a tractor motor that will never win any races, any way you slice it.
 
This is for some deeper discussion for me as I under stand how to do it. and have the desmog guide for the 3fe.
1. what I know, the 3fe is designed to run desmoged, I will get better power, smother running, and possibly better over all mileage but this is debatable and not really important.
2. I have a good idea how to do it and what parts are needed. per the desmog guide floating around the forum. if anyone wants it ill be happy to send it to you.

what I need to know/ want to discuss
1 is there really a reason to remove the smog pump if its not connected to anything.
2 how long does it really take for the ecu to learn, and how quickly will it forget when battery is disconnected.
3 why are most so scared of it
4 is there any real reason not to other than if you live in an area that tests emissions
5 is it possible or worth it to track down a non us ecu, or are there any better after market ecus that could be used and maybe use a mas air flow meter vs the afm which is impossible to find new and when you can its outrageously expensive.
Will the desmog process be similar enough on a 1fzfe? My problem with the smog system is not so much what it does to the engine but that all the hoses and pumps etc are always in my way and make my engine look dirty for lack of a better term. Better mileage and a better running engine sounds great though
 
As I understand it. Whether or not there is better performance. If all components are original you may see a slight increase in mpg or performance due to old broken components causing a performance drain. How ever for me tha major reason is the engine is a tractor engine and it doesn't matter what u do it's gonna be bad for the trees and if u own one u probably don't care. It's a pet of automotive history and if you want real performance and better trees swap the engine for a new v8. And 2 I already have some fuel and idol problems so it will be elimating dozens of fail points and reliability is my main concern. If I get better performance than great but my 3fe already drives better and faster than most people describe. I can get 60mph in about 8 secconds and I don't really wanna ask why. Though I've never had better then 10 mpg in traffic or highway it's a dead 10 mpg which with my fuel issues has dropped to 8. which I think is some of my old ecu sensors which I'm in the middle of replacing
 
A low, sumbling idle is what's driving my interest in the desmog, or at least testing it to see if it makes a difference. Otherwise it runs pretty good and my mileage runs 13-15 mpg.
 
mine idoled at 2000 rpm and would stall once it got up to operating temp. plus once it was hot it wouldn't start at all. I'm pretty sure I've narrowed it down to multiple failing sensors as now that l have toyed with a couple it won't run longer than 10 seconds and dies no matter what the temp but starts beautifully, lol can't have it all I guess. I just want to rule out vacuum leaks and id rather desmog than replace all those s***ty sensors and hoses if I already have to go to the trouble as all the hoses are cracking now. the Memphis heat doesn't help old rubber.
 
As I understand it. Whether or not there is better performance. If all components are original you may see a slight increase in mpg or performance due to old broken components causing a performance drain. How ever for me tha major reason is the engine is a tractor engine and it doesn't matter what u do it's gonna be bad for the trees and if u own one u probably don't care. It's a pet of automotive history and if you want real performance and better trees swap the engine for a new v8. And 2 I already have some fuel and idol problems so it will be elimating dozens of fail points and reliability is my main concern. If I get better performance than great but my 3fe already drives better and faster than most people describe. I can get 60mph in about 8 secconds and I don't really wanna ask why. Though I've never had better then 10 mpg in traffic or highway it's a dead 10 mpg which with my fuel issues has dropped to 8. which I think is some of my old ecu sensors which I'm in the middle of replacing
8 seconds to 60 mph, eh? Musta been one helluva hill. Motorweek tested a new one in 1989 at 14.2 seconds.
IMG_4845.PNG
 
Yeah - My 1990 five oh Mustang was always advertised at 6.2 seconds 0-60. Nearly double the weight and 2/3rds the power.......
 
Also my MPG increased and it ran better. But if your 3fe is well running and without issues my guess is it won't improve. But I do believe taking out the EGR will increase MPG. Putting only fresh air into the combustion cycle is better than previously burned poison. My belief.

You may be right, but the point of EGR is to slow the combustion process (by introducing a less combustible gas) to prevent spark knock and lower combustion temps to prevent NOX formation.

Regarding desmogging, with a totally stock engine, at least you can troubleshoot using standard procedures, without wondering if your mods are affecting engine performance. It's a tractor motor that will never win any races, any way you slice it.

Most tractor motors are pretty simple though, and lack much in the way of emissions controls...;)
 
Ok maybe I'm wrong it's a gestamate and probably a over estimation maybe Is 13 I just know it's faster than others I've driven and imma time it as soon as I have it running again hahaha. You guys are the worst! Hahaha I love it here
 
Removing the air pump silencer will open a big pile of room in the engine compartment (behind the driver's side headlight), and won't hurt a thing. That device is one of the dumber space-sucking items under the hood. I cannot tell that the air pump is any louder without this fine device.
 
Is that the little cylindrical canister behind the headlight?
 
Removed all the smog system from my 3FE when it had 280K miles, and it ran the same before and after. on the next two motors (one with 5K mile and the other currently at about 6K) neither have any smog components either. Stock USA ECU is fine, only possible issue is if you have a California ECU it might want to see a reading from the EGR temperate sender? I don't actually know though.

Nice benefit of removing the smog pump is that you can put a second alternator there.

I pulled everything off mine the other week because the air rail had melted the wire harness and was causing a lot of hate and discontent. While I had the upper intake off some things went away.None of it worked right before so no change in running, power, mileage, etc. As others have noted, you pick up a lot of space without that stuff in the way. Yes a CA ECU will throw code 71 when the EGR isn't working. Mine did before and it still does. I haven't fixed that yet - but you should be able to replace the sensor with a resistor of the correct value to keep your CEL off.


a 10k ohm resistor will give the ecu what it wants to keep the egr gas code from being thrown. it just needs to be wired in parallel to the sensor at any point in those two wires, which means it can happen under the harness wrap and not key a smog tech to the situation...
 
Some of the emissions components on the 3F-E are actuated by engine vacuum. The vacuum is the force that pulls a diaphragm that makes something move.

The vacuum travels through the thin black vacuum hoses to wherever. When a ball bearing (3/16" for oem vacuum hose, 5/32" for silicone vac hose) is jammed in a hose, the vacuum is blocked which disables it's attached component. Blocking certain vacuum hoses is how some emissions components are disabled.

(BTW, an air gun bb is too small)


but a skirted pellet is JUST RIGHT ;)
 

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