Jeezis, this is becoming.......beyond fricken tedious. Any one here able to tell/show me the correct location/pin number where the black K/S sensor wire finally arrives at the ECU? My Haynes manual only shows one 'Later Model' general wiring diagram (page 12-17), but their drawing/schematic of their ECU doesn't match mine at all. According to their diagram, the K/S pin/terminal is the second one from the left, on the bottom row where the release tab is on the largest of the 3 harnesses. That drawing shows 18 different pins. Unfortunately my harness (the largest of the three) has 26 pins. I apologize for bugging you guys again but I've been trying to find wiring diagrams all morning with my friggen EyeFone, but to no avail. Just trying to kill this code and drive this truck out to my son in Wisconsin this week.

'Cuz I'm going for my Dad of the Year award......

 

The middle connector, 4th pin back on top row. http://personal.utulsa.edu/~nathan-b...e/102engin.pdf

 

Bing. Go!.......

 

Dateline, San Pedro, California. (Code 52 Killing Update)....

1). Relocated knock sensor to driver's side engine hook bolt hole.

2). Cut black wire for knock sensor 2" from the ECU. Crimped on a female spade connector on it, and a male spade connector on one end of some #16 stranded copper wire. Mated the two of them, wrapped the crap out of them, plugged in all three ECU terminals and reinstalled ECU box.

3). Ran the other end of the wire thru three feet of 3/8" o.d vacuumn line. Drilled a 17/32" hole through fire wall (just behind the ECU) and another like hole up thru the top of the fender well (just under the inner edge of the plastic fender well liner). Installed 2 rubber grommets in both holes, then ran vacuumn hose up thru both of them and into the engine room. Tucked most of exposed vacuum line in wheel well up behind plastic well skirt.

4). Ran rest of wire over to the knock sensor harness (along the fire wall). Cut the black wire at the knock sensor-to-ECU harness and again crimped on two spade connectors. Wrapped the hell out of them with tape and then covered all of the new wire with black plastic spiral wire protector.

5). Went on 45 mile test drive, thru town and on the freeway. No CEL. Tranny now shifts better, over drive works all the time, gas gauge needle doesn't spin counter-clockwise and engine purrs like a happy cat and has some extra testicles. Big happiness in Ricky Land. Wisconsin, here I come......

 

Still fixed?

 

Funny that you ask, Bob, I just literally pulled into Cedar City, Utah about 10 minutes ago. Put 431 miles on her today (from San Pedro, So Cal) and she's running like a striped-assed-ape. So far. Better go find some wood now and give it a good knock.......

 

Here's a little update for anyone who cares----just pulled into my son's driveway in Wisconsin last night after a 2,051 mile road trip that began in L. A.. The truck ran almost perfectly the entire way, except for the over drive, which wouldn't engage/stay engaged maybe 33% of the way. Which was fine with me, cuz at 3100 rpm I was still moving at 60 mph, and I was in no huge rush. The only other issue I had (but seemed to have no bearing on gas mileage or performance) was that the CEL came on three different times, for maybe total of 6 hours. I pulled codes each time (to make sure it wasn't the evil 52 coming back to haunt me), and all 3 times I got Code 71. EGR and/or vacuum hoses, I believe. But the light has been off for the last 700 miles, so I think we'll disco the battery cable and try to clear it. My son will only be driving this thing around town for the forseeable future, so we're not gonna sweat it right now.

Ok, now here's the better news-----L.A. to Denver to Des Moines to Whitewater, Wisconsin was exactly 2051 miles, though the 'tripometer' says it was 1917 miles. Which I don't get, except that there's 31" BFG's on her. Anyways I used exactly 120.83 gallons of gas on this trip ($463.22), which equates to exactly 16.97 miles per gallon. Which made me very happy, given that I was figuring it'd be more like 14.5 mpg's or so. I consider this a win, especially on a twenty year old vehicle with 184,000 miles on the clock.


So thanx again for all your help, Folks----much appreciated......

 

So, on a 1990 toyota pickup, 3.0, if I disconnect the KS harness at the pigtail under the throttle body and check for continuity to ground on the wires running back to the ECU, only the shield should go to ground? Or will the KS wire also ground thru the ECU? I know the pigtail is crap but I would really like to avoid R & R on the intake manifold if it turns out to be a bad ECU.

 

Shield should always be grounded. If I remember right, it's grounded at the same location as the ECU ground, but it's not grounded through the ECU.

There should be continuity between ground and the shield. There should NEVER be continuity between the signal wire and ground.

 

Hmmm, I get 3.4K ohms to ground when I test the wire to the ECU. Drops to open when I pull the connector at the ECU.
Another question. Since I am going to pull the manifold to replace the pigtail, can I test the knock sensor by hooking up my voltmeter and placing an electric engraver (60 hertz) on the engine block?

 

Sometimes, if you hook up one probe to ground, the other to the pin on the knock sensor, if you just tap on the block with something metal you will see a brief voltage spike on your DVOM. Probably be easier to see on an oldschool analog meter.

Short answer- yes, a slight voltage spike can be seen. Not sure if your engraver will do it or not, as the KS is tuned to max timing retard around 7kHz.

 

Thanks

 

How can you test the Knock Sensor? I have mine out of the venicle and would like to know if there is a test for it before spending another $150 on my 92 3vze. I replaced wiring, ECU and I am about to replace the entire truck. I need to fix the code 52 so I can license the truck as I am in Cali..

Are the risks significant to doing the relocation? I really don't want to open this beast up again.. EVER!

 

The only way I know of to test a ks, and get absolute resluts, is to use an oscilloscope(spelling?)... U can try with the multimeter, but I believe it has been proven that it's not an accurate test.

If u wanna fix the code 52, open the beast up again.... sorry, I know its not what u wanted to hear, but really, it's not that bad... I think last time I had mine apart, it took me about 4-5 hrs. The risks to relocating are significant... if U have a knock on the other side of the block (yes the ks will pick it up, but not at the correct frequency) the timing may not get retarded enough, which can make things go BOOM...lol

 

 

thie entry removed by submitter

 

can i fix mine with out the original connector my busted i have a new harness but the main harness plug busted can u help me my knock good but the wiring is brok

 

Grab a new connector from the dealership. If i remember correctly, the PN is 82219-89103, but doublecheck with your local dealer or www.1sttoyotaparts.com to verify compatibility. If the wire after that connector is toasted, rewire with a good coaxial/shielded cable. Make sure to properly ground the shield.

 

Can any of yal tell me what the part num of the main connecter on wiring harness on 1990 4 runner 3.0L is that connects the harness to the knock harness plz my shattered help

 

You should just go to your local Toyota dealership and I'm sure they'll be more than happy to help you. However, if you read my previous post, I'm 99% sure that the one you need is 82219-89103.