The 3.4 uses a MAF (mass air flow sensor). The harness for it comes off the 5VZFE engine harness along with the igniter harness (also shown in the pic).

 

on elvotas post on page seven there is a post that says if you tie the maf wire from the 3.0 hareness( i am guessing the body harness)to the tc pin on the 3.4 ecm that the fuel pump will work when in the run possition. the post wasnt by elvota it was someone else, 7th page about 3/4 way down, it was elvota was having trouble and it was an igniter wire problem.

 

tc pin... is that FC pin, from the 3.4 relay to the FC pin on the 3.4 ECM?

Are you referring to the following comment?

Willcipher was giving me a method to test the fuel pump for operation, to make sure it was at least turning on. The guess was I had a problem with the ground side of the COR, since the 3.0 and 3.4 ECM's handle the fuel pump differently and that my motor wasn't firing because of no fuel.

 

yeah thats the fc pin, my bad, directley above that post willchipper said that the fc wire from the 3.4 ecm needed to be connected to the afm wire from the 3.0 body harness because the 3.0 maf operated the cor for the fuel pump, i didnt know where the cor relay was but i will check it for a ground and see if that is my problem. elvota , did you use the 3.0 cor? i thought i read that you used a 3.4 relay but i could be wrong. again thanks for all the help guys

 

I ended up going with a COR from a 3.4, but since my problem was actually with a loose ignitor wire, either COR would most likely work.

Do you have your OBDII port hooked up yet? Some local auto parts stores will rent or loan out a scanner. Would be helpful to see what codes your computer is seeing. That alone saved me hours and hours of work. Solved my issue right away.

Try to get one hooked up and post the codes for more help if your COR test fails.

 

well i traced down the wire to the cor, grounded it to check like willchipper said and the fuel pump would now run with the ignition in the run position, i then connected the fc wire from the ecm turned the key, the 3.4 started and continued to run, that was the i started jumping and hollaring for joy, the engine ran pretty good, has some hesitation but i dont have the 02 sensors hooked up yet and i am still working on the vacume lines, i will keep you guys posted, i will be wiring up an obdII connector so i can check the codes when i get all my loose ends together, i am sure ther will be some codes because i am not running the evap. thanks

 

got to do some more work but it is getting there. it seems the engine is idling pretty high, i havnt let it get warm yet and also has some hesitation, it could be that i dont have my exhaust hooked up yet, i am waiting on my muffler and cat to be delivered. maybe when the ecm gets an o2 reading the idle might straiten out along with the hesitation. i will keep you guys posted

 

i took it on a road test today and the truck runs great and has plenty of power. i solved the high idle problem, it was the iac valve, took it off and cleaned it, my idle dropped fro, 2000 rpm to 740 rpm, as far as the hesitation i forgot to hook up a hot wire for tha maf. i still have to hook up the tach and speedo but thats gravy. has anyone figured out how to wire up the ac amp to run the air cond? i want to thank everyone for there help. if it hadnt been for yotatech and you guys i wouldnt of thought about doing this swap. also were do i hook up the purge line from the 3.0 charcoal canister? i dont have the evap stuff or an egr. are any of you guys running without an egr?

 

Nice job. Always more rewarding to do a swap and get the 3.4 to actually run.

Maybe try to get a hold of "FallGuy" here on YT. I think he has done some AC work after the swap.

My motor didn't have EGR from the factory. I have some EVAP stuff on page 4 of my swap. The answers you need should be there.

https://www.yotatech.com/forums/f160...85/index4.html

 

I think you mean Brian "thefallman" https://www.yotatech.com/members/16525.html

 

Oh yes... sorry. "The Fall Guy" is some 80's TV show that randomly popped into my head.



Contact "the fallman" for your AC questions. Recall "The Fall Guy" for other reasons.



The 80's rocked.....

 

does anyone know if and where i can get some heavy duty rear coils to fix the sag in the rear? i only want about 1 '' to 1 1/2 '' at the most, i dont want 2'' or higher. i use this rig to pull my boat. i want a small lift so i wont have to crank up the tbars to make it look right.

 

Coils for the rear.... don't you have a pickup?

ZUK does a coil spring mod for leaves:

http://www.gearinstalls.com/miked.htm

Maybe read through there a bit.

Best thing to do though would be to post your question in the main "86-95 tech" forum so it doesn't get buried or clutter up the 3.4 thread.

 

Main thing with making the a/c work is number one doing your wiring right between your engine and body harness. it will work with out the 3.4 a/c amplifier it just wont kick off when it should and some other issues. next get a 3.4 a/c amplifier and swap it with your make sure and get the harness plugs for the amplifier then wire it in to your harness. the 3.0 and 3.4 used differnt signals to control idle up and down and some other things

 

where exactley is the ac amplifier on the 3.4 vehicles? where are they on the 4runners with 3.0. is it a relay or a thermostat or a control box. i have never had to work with an ac amplifier, only the main ac components.

 

Hey guys its been awhile but i have been busy at work. I finally got some time off to finish my 4runner. i got everything workin but the cruise. got my sterio put in, and my 33's on. This thing rides and runs great, lots of power and torque. sterio sounds great to, i used 1'' spacers in the door and installed some 5 1/4'' components with no problems, put some 6x9 in boxes in the rear with a sony 444 watt amp. here are some pics of my completed ride. thanks guys for all your help

 

go job man!!
let us know how tha CC works out!!
:thumbs:

 

ac amp is on the cab side of the condenser at the bottom under your dash on the 3.4 and it is on the top of the condenser on the 3.0. in both cases they are small circuit boards

 

Didn't we tell you that you'd love it? Yeah, that's right...we did...

 

Condenser? You must mean the evaporator. The condenser is in front of the radiator.