Lardog

First post.
Help pease.
My son just bought a 1992 Toyota 4x4 truck that has a 3.4 engine in it.
He tried to change the spark plugs and there appears to be a piece of rubber or foam down the tube and around the plug and he cant get a wrench on the plug because of this piece. How do you get this rubber piece out of the tube?
I know this sounds dumb but I dont want to destroy anything.

Also does anyone have a wiring diagram of the computer for this engine swap?

Lastly The idle on the truck is a little eratic and I noticed that when you step on the clutch the idle goes down Almost to the point of stalling the engine does anybody have a clue on what this might be??

Thanks

Lardog

yodathespian87

Welcome to Yotatech.
Here is a link with a few diagrams but the problem is with the 3.4 engines they are year specific so wires may be different colors or spots due to the year differences. So I would suggest going to
https://techinfo.toyota.com/techInfo....toyota.com%2F

This is whereI printed off all my diagrams for the exact year of my trucks. Save all the files you can on your desktop and then you can go back and look at them when ever instead of paying to get on all the time.

As for the little piece of rubber I don't really know cause there isn't a lot of space by those spark plugs.

Lardog

Thanks for the reply.
I did did download everything for the engine and truck boy what agreat site.
The rubber piece surrounds the plug like it came off of the long connector that goes down the hole. when you try and put a wrench on the plug the rubber stops the socket from getting down to the hex.
I am going to try some long tweezers and see if I can get the rubber piece out.

Thanks

vital22re

iTrader: (2)

sounds like the boot for the coil pack. if its not stayin on the coil, its time for a new boot then.

Tragic Drive

Welcome to Yotatech.

Here is a schematic I did for a 96 3.4 to a 95 3.0 manual transmission 4Runner.
https://www.yotatech.com/forums/f160...s-here-164858/.
It should be accurate for most years up to I think 98 or 99 where Toyota started using wideband o2 sensors.

Long nose pliers will help get that boot off the plug.

Since you just bought the truck do the basic tuneup stuff and check for vac leaks.
One more link for ya here https://www.yotatech.com/forums/f160/

Good luck.

Lardog

Ok thanks all for the replys.
So my son and I are making great progress on this truck and its a good one for us to work together.
When the truck is first started the engine revs to about 1500 RPM and slowly gets down to an idle of about 700.
this takes about 4 or 5 minutes. I pulled the TB it was filthy and we cleaned and reinstalled and the idle is much smoother but the hi revs at startup still exists.
When the conversion was done (by whoever) they took the original truck harness and spliced in the new Computer and proped it up down by the passenger kick panel. He did solder the connections the computer case is not bolted into the truck. Is this a potential ground problem?
I just got schematics for both truck and 2000 tacoma engine and will diagram how he wired the computer in.
At a quick glance I notice that there is only 1 02 sensor hooked up. He put a new exhaust system on and it only had 1 bung for an 02 sensor I guess I need to figure out how to drill the pipe after the cat and hook up the other 02 sensor. i dont think this would affect the hi rev problem we have but I am sure it will affect the engine air fuel ratio.
I am hoping the hi rev problem is not computer that is why I want to go back to basics first and see if I have a sensor issue. Does anyone have any Ideas that would help solve this? I searched threads and cannot find anything that relates to this problem. I think if it was a vacuum leak I would have Hi revs all the time.
Thanks

Lardog in Sunny Minnesota.

ozziesironmanoffroad

ya, if the ECU isnt bolted to anything, then id say u got a BIG ground problem.
man i wish i had gotten my truck with a 3.4 already swapped in. u guys r lucky. im envious!

Lardog

Granted we didnt have to do all the work but I would have rather done it myself. first of all some of the work that was done was just a rig not very pretty at all.
I am spending a lot of time trying to fix what this guy didnt do. I just finished regrounding the whole truck, there were no gronds to the frame or body. the engine ground were loose some were broken but they are solid now.
I have alwas been a cherokee guy and my son has always wanted this year TOY. I know almost all about the problems and fixes of the XJ and now I am learning about his 92 pickup. I have to say I am impressed with how solid this truck is, so i feel its worth the time and sons expense to make this a great rig.
Oh sorry here is another question. I was reading some of the Factory service stuff and they talk about something called a Dashpot that is a device that is hooked to the Throttle Body. I dont have on on this truck. What is it and what does it do????

Thanks all

Lardog

Ron Helmuth

High revs at startup is standard procedure. The engine will reach a warm up point and then throttle back to normal idle. There is a substantial amount of "whoosh" noise and again this is normal at startup.

Tragic Drive

As far as the ECU goes mine hasn't been bolted to the body for 4 years and over 20k miles and no problems so far, it has its own ground wire. I would however recommend bolting it down.
I think you would pop a code if you didn't have the 2nd O2 sensor. He might have used an O2 simulator instead or wiring one in you might have to look around for it.

Lardog

Ok just got home from work.
I found the wire stuffed up in the frame I just need to figure out how to mount another 02 sensor.
The truck is throwing a code but I dont have the connector to it so I will go to an auto parts stor and get it for free I hope. I asume you hook up to the connector that is bolted to the engine?????????? he also left the original port hanging in the glove box. So as I said back to basics and see what the unit is mad about.
I see Ron responded about the Hi rev issue, Is it supposed to rev that high and for 4 minutes. Isnt that going to be hard on the engine during those cold Minnesota mornings?
I dont doubt what you say it just seems to be pretty radical.
Wow i love the fully boxed frame on this truck. Here is my next newbie question. Does anyone know a good place to buy a set of standard leaf springs for the truck?? I want a good set but I dont need anymore lift. everything I look at on the web is for lifts.

Lardo

Tragic Drive

Here is a thread with pics about the O2 sensor mount.There might be an easier way though. Its the 2nd to the last post on this thread.
https://www.yotatech.com/forums/f2/q...4l-swap-68154/

You need to have the OBD2 connector hooked up for the shop to read and clear your codes.
The one in the glove box is probably where the previous owner landed the new connector. I don't recall Toyota using the glovebox for any ECU access points.
If the one in your glovebox is shaped like a trapezoid you should use that.
If that is not the OBD2 connector I posted a link earlier with the schematics/terminations for your connector.

Good Luck

Lardog

Thanks
Well my son took the truck down to the local parts shop and they hooked up the scanner.
You are right, I thought the connector bolted to the engine would be the OBDII port but it is not. The OBD II port is the one that he put in the glove box and now that I know that I will mount it properly and clean up the wires.
I guess the one on the engine was OBD I and it must be part of the original harness from the 3.0.
Anyhow I spoke with my son on the phone and he said there were about 20 codes showing and most of them sound like the engine and computer had an automatic trans.
I will review what we found and post later. I am sure this will raise some questions.
Thanks again
Lardog

Lardog

I posted a message to you directly on the private section. being a newbie I am sort of lost here. but I need some help on your schematic.
Thanks
Lardog

Tragic Drive

Responded, You should also request a moderator move this to the 3.4 swap section. You might be able to find more answers to your questions.

Lardog

I was asking because I was trying to understand your schematic.
I didnt know if I was looking at connectors on wires or in the CPU.
I have been downloading the 2000 Tacoma engine and the Truck itself so I almost have that together.
Electrical is what I have the most experienc in so I am not worried about getting all of that going.
1992 Toyota truck or pickup depending on what I am reading.
2000 tacoma engine 5 speed manual.
Runs strong.
codes scanned yesterday
PO171 system lean bank 1 I think is from not having Two 02 sensors
PO141 heatre circuit again I think an 02 sensor problem
441 Evap incorrectt purge flow Thats for this weekend.
710,753,758,773 all seem to be AT issues which we dont have.
Being a jeep Cherokee guy I have been tossed into the world of toyota mods, whuch is great fun espacially with my son. Just trying to get him on the road with a good ride as quick as possible.
I appreciate all of you help.
After codeissues all I have is back up lights to solve and he can start cruisin.
Oh I have never taken my vehickles to a dealer I prefer the challenge of fixing my own.
And I agree that this thread should be moved I just dont know how to contact the Moderator to do that.
Again much appreciated
Lardog

Dan.3

Idle is normal. Dont be misinformed about the ecu being grounded. Newbies unlike yourself like to post information they have absolutely no clue about. My ecu is just hanging underneath my glove box by zip ties.

What is the labeling of the ecu? Does it read 4x4 MT or AT? Might even have 4x2. If not obvious already the MT is Manual Trans and the AT means Automatic Trans. Im guessing by the codes that it reads 4x4 AT. Nothing to be alarmed about. Just explains the codes.

Except for the evap, the truck seems to be pretty healthy. I have been running mine with out the second o2 sensor as well. Im not to worried since mine is not a daily driver. If it was I would probably install it.

Its kind of odd that the OBD I is still in the engine bay. If I remember correctly I thought it was attaced to the old 3.0 engine harness.

Lardog

Thanks for getting in on this.
I figured the grouding of the ECU was ok snce I see wire ground wire in the schematic going to the cicuit board inside the case. and the truck is running good or should I say great. I learned that this engine originally was super charged. I will chek the case to see what it says. This weekend I am going to try and mount the ecu somehow just to keep it and its wires safe from feet.
the guy that did the MOD was not a neat freek so I now have the scheme on the ECU and can trace what he connected or didnt. Finally.
Thanks for the reply
Lardog

Corey

iTrader: (1)

Thread moved for best exposure.