0-100 - 1985 4runner Build Thread

and now it seems like the weird revs issue has magically disappeared... huh. [/QUOTE said:
This crap... right here... is why i will never fully trust and love an EFI system. In the back of my head I always know there is something weird that is going to pop up that I wont be able to diagnose because magic circuits and black boxes.
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I think I have narrowed the problem down to my knock sensor being bad. The truck drives great until I hit around 3k (sometimes a little less, sometimes a little more) revs. Once I hit that point, there's a very slight, yet noticeable jolt, and then the trucks revs seem off and power is lost, especially uphill and in 1st gear (I'm guessing the timing is being changed by the sensor). The reason I think that it's the sensor and not my engine is because if I drive slow, like when I went wheeling for example, the truck runs great and there's no CEL, but when I drive somewhat fast, boom CEL appears. Now I have to find a replacement knock sensor that's not $200+ :(
 
I'm now wondering if a knock sensor for a 1988 4runner will fit my 85...? They seem to be a LOT cheaper. I would assume it would fit?
 
PlanetExpress said:
How to test knock sensor - YotaTech Forums

Post #4 and post #19

I'd try this before I spent the money on a new sensor. Hopefully that works!
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I checked out the wiring, and as far as I know it looks fine? I suck at wiring things so I have no idea how to replace it. Do I just get any type of wire and cut the old one out, put the new one in its place or do I need to buy a specific knock sensor wire?

And would an 89 22re knock sensor fit my 85?
 
TheManOutside said:
Do I just get any type of wire and cut the old one out, put the new one in its place or do I need to buy a specific knock sensor wire?
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According to Yotatech Forums, you need a shielded wire. Something like this: SHIELDED WIRE MIL-C-27500 - WHITE from Aircraft Spruce

Also, sourced from a pertinant thread on 4X4Wire.com: "Make sure that you have a good ground to the engine block. Since the knock sensor's body completes the signal path to ground (engine block).

Also I assume the knock sensor wire is the same or similar to the later years, where there's an inner conductor and then an outer braided shield wire.

The outer shield is connected on the ECU side "only", which the terminal it's connected to is a sensor ground, so make sure the ECU has a Good ground as well.

The inner conductor goes from the knock sensor terminal to the ECU's KNK input terminal. Double check for continuity while wiggling the wire around to verify that the wire isn't going open (broken wire) with the movement of the engine when it's running." -Anonymous

I'm just posting that because if i were in your shoes i would avoid having to throw money at sensors for as long as possible by troubleshooting.

TheManOutside said:
And would an 89 22re knock sensor fit my 85?
Click to expand...
Wish i could help you here definitively. I've searched the OEM suppliers and it looks like your Knock sensor was utilized from 85-86 and is compatible with an 87, whereas the 89 knock sensor works from 87 to 89. There were no signal specifications so i cant determine if the knock sensors have a different output value that the ECU interprets. If you are dead set on replacing the sensor i would suggest is checking your local junkyard for an 85-87 4runner and seeing if the sensor is still in the truck. $200 + is a lot for a sensor, especially if you aren't sure if the original is defective.
 
PlanetExpress said:
According to Yotatech Forums, you need a shielded wire. Something like this: SHIELDED WIRE MIL-C-27500 - WHITE from Aircraft Spruce

Also, sourced from a pertinant thread on 4X4Wire.com: "Make sure that you have a good ground to the engine block. Since the knock sensor's body completes the signal path to ground (engine block).

Also I assume the knock sensor wire is the same or similar to the later years, where there's an inner conductor and then an outer braided shield wire.

The outer shield is connected on the ECU side "only", which the terminal it's connected to is a sensor ground, so make sure the ECU has a Good ground as well.

The inner conductor goes from the knock sensor terminal to the ECU's KNK input terminal. Double check for continuity while wiggling the wire around to verify that the wire isn't going open (broken wire) with the movement of the engine when it's running." -Anonymous

I'm just posting that because if i were in your shoes i would avoid having to throw money at sensors for as long as possible by troubleshooting.


Wish i could help you here definitively. I've searched the OEM suppliers and it looks like your Knock sensor was utilized from 85-86 and is compatible with an 87, whereas the 89 knock sensor works from 87 to 89. There were no signal specifications so i cant determine if the knock sensors have a different output value that the ECU interprets. If you are dead set on replacing the sensor i would suggest is checking your local junkyard for an 85-87 4runner and seeing if the sensor is still in the truck. $200 + is a lot for a sensor, especially if you aren't sure if the original is defective.
Click to expand...

Thank you so much for your help so far! I appreciate it!

I will try and check the continuity of the wire this week if I can get around to it. As far as the actual sensor goes, I was planning on going to a junk yard HOPEFULLY (probably not haha) by the end of month and see what I could find.

Other than that, the truck hasn't exploded yet, it's just really annoying because after I hit 3k + RPM or go uphill the check engine light comes on and the timing gets set back to 0 degrees or whatever.

OH, and thanks for the link to that wire! I actually had trouble finding that for some reason.
 
I don't think my tires are supposed to tilt like this...

VhP2SBH.png


I just noticed today that I have quite a bit of positive camber (trust me, the photo does not do justice). I don't really know how this happened? I always had a very small amount positive camber, but damn. lol. How do I fix this? Should I get an alignment? :confused:
 
Jack up the front, grab that wheel and shake it, see if there's play in it. Could just be the main nut on the end that's come loose.

And you have an '85 22RE, right? Just loses power after hitting a hill or holding steady at 3200rpm or a bit higher?

It might just be this thing:

6267347128_1ff7d9f0a9_z.jpg

image stolen from the internet!

I used to have all sorts of issues running up hills when I still had this thing installed, it would be fine then all of a sudden, its like someone hooked a thousand pound anchor to the back of me!

This is the air flow valve, I guess it does some weird heating of the throttlebody which reduces power in the system. Hot air = no power.

Not saying this is the issue with yours, but it has been known to rob power when a load is present. Replacing the whole intake manifold, throttle body and eliminating that valve is what I did, the '89+ engines had a different efi setup that works much better than the original setup. My truck has been solid for many years, and I'd get in it today and drive it cross-country any time!
 
flyinhawaiian01 said:
Jack up the front, grab that wheel and shake it, see if there's play in it. Could just be the main nut on the end that's come loose.

And you have an '85 22RE, right? Just loses power after hitting a hill or holding steady at 3200rpm or a bit higher?

It might just be this thing:

6267347128_1ff7d9f0a9_z.jpg

image stolen from the internet!

I used to have all sorts of issues running up hills when I still had this thing installed, it would be fine then all of a sudden, its like someone hooked a thousand pound anchor to the back of me!

This is the air flow valve, I guess it does some weird heating of the throttlebody which reduces power in the system. Hot air = no power.

Not saying this is the issue with yours, but it has been known to rob power when a load is present. Replacing the whole intake manifold, throttle body and eliminating that valve is what I did, the '89+ engines had a different efi setup that works much better than the original setup. My truck has been solid for many years, and I'd get in it today and drive it cross-country any time!
Click to expand...

I will definitely look into that! however, I don't think that that's the issue, because I only get poor power whenever the CEL comes on, and it's giving me code 12 for knock sensor, so I think my sensors just bad and it's misreading something and setting back my timing to 0.

As for my awesome stance, I will jack the truck up when I get the chance and see what's up. it's probably what you said, I would hope so at least haha I'm not in the mood to fix any axle stuff :p
 
Ordered a knock sensor today for a whopping $35! WOO I got it from a junk yard in Colorado called Yota Yard. It should ship tomorrow. Let's just hope it works :pray:
 
PlanetExpress said:
That is a hell of a deal. If it doesn't work at least you have a spare, i doubt you would ever find another for that price
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That's pretty much why I bought it! After only seeing $250+ why not try one that's $35? It is used, but who cares. As long as it works (hopefully).
 
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i've been too lazy to post anything here recently. anyway I got my new knock sensor :

d2pNOEC.jpg


1mDehIr.jpg

Old vs. New

Put it in a voila! Nothing happened. still have CEL code 12, still slight loss of power and mpg, bla bla bla. I guess the issue now is either in the wire or the ecu, which I have no idea how to figure out, so this will be interesting.

my steering is also beginning to make me angry, I've been dealing with it for a while but now i'm mad haha. it's super sloppy, has a lot of play, really sketchy to drive. I tried adjusting the steering box but the flat head screw part/bolt is frozen to the nut it seems so I can't actually adjust it. awesome! :ybrick:

and my tires skip when I turn :D what's going on hahaaa
 
My 3rd gear is starting to go out... it's been grinding a little and now it just pops out whenever I shift into 3rd. I think it might just be the shift lever ball seat but I'm not too sure.
 
Thefishguy77 said:
Throw a new Marlin seat in there and see if that fixes it


Sent from my iPhone using Tapatalk
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I'm gonna (hopefully) change my transmission fluid this weekend. im gonna check my current seat and see whats up, but yeah I'll probably end up getting a marlin anyway. :nod:
 
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