Desmog 92 FJ80 HUGE MPG increase.

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I did mine when I first bought the thing, but never checked milage cause I only did short trips. I moved back to New Mex from Texas acouple months back and was averaging around 17mpg driving back. I was getting around 400 miles to a tank and only spent about 150 bucks on gas on a 950 mile trip. That was with a desmoged and part timed 4wd 92 with a J lift and 31's, now 37's. Made me decide to keep the old 3fe in there, now I just need 5.29's a junkyard turbo and maybe that 2f block my boss has sitting there.
 
What did you guys do with the fuel psi regulator did you leave it hooked up. I wanna eliminate all the stuff including electrical vacuum solenoids on the 3fe's fender. IS this possible or must i retain the one pertaining to the fuel psi regulator. I have already removed all egr componets including egr valve air pump air injectors etc. afraid to run it with not knowing about the fpr removed all the vacuum lines that lead to the fender.
 
Does this only apply to gas engines or can this be done on a diesel as well?
 
A 50% increase in MPG from block vac lines and bypassing the smog pump? As much as I hope you're right, I think you're confusing causation and correlation.

Me too.

I'm throwing the BS flag. I have done the same thing: diable the EGR and air injection and I never saw more than a few % (less than 5%) after driving a year, not just two tanks.
YMMV (literally)
 
newbie question about hose

i disconnected a hose to find the same diameter caps and forgot to reinstall it. i noticed instantly that my throttle response was better and i also got slightly better gas mileage! if i just left the hose off and did nothing else, am i going to damage anything? also, am i letting exhaust gas flow into the engine bay by doing this?
photostream
:doh:
 
I am in a no check state and just looped all e the hoses cause it does not matter if they look like they are hooked up. Also put the short belt on etc. I cant say I have gained a thing and it has been like that for months. Still get 10 - 11 mpg still a 3FE.
 
I removed only my cats, puy new o2 sensors and have gotten 17mpg on the last 2 tanks. I havent removed the EGR.
 
Can someone put pictures up of what lines to loop and what lines to block? I was ready to do this but the pictures are gone. A little help please..
 
So I bypassed my air pump using the method described above and I got major pinging, whats the deal?
 
The EGR system cools the pistons. Pinging is usually caused by pre-detination of the fuel in the cylinder. If you had other contributing factors such as running hot or poor fuel quality, then you could have just crossed the line between ping and no ping. You can try some timing adjustment or higher octane etc.
 
Higher octane should help. I had to use that because I would get a pinging/heavy grind on acceleration. After getting the valves adjusted, I was able to switch to cheaper gas because there was no more noise.
 
So, I'm bringing back a dead thread… but can I do all the under the hood stuff and then just leave the cats in place for now?

Yes. I did everything under the hood and left my cats in place. Had them pressure tested at a local performance muffler shop and they tested exceptionally well. Didn't feel any need to cut them out.
 
what is the pathway of this belt replacement on the '92 3FE? TR22525? does it need to turn the alternator? doesn't look long enough
 

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