midiwall

Yeup, you should definitely be able to see it happen. Clear the code, fire up the engine, and watch the timing. As soon as the ECU sees (actually "doesn't see") the sensor, then it should pitch the timing down.

midiwall

Well, on the 3.4 it's an OBD II vehicle so I can do it with my OBD II reader tool. Dunno an easy way to do it on the 3.0...

Does the light come back on _immediately_? The ECU on the 3.4L won't throw the code until it doesn't see the sensor with the engine between 1700 & 3000 RPM. If the 3.0 is the same way, that can give you some time to watch the action when using the light.

Dave Mooney

Yes Mark: Once I clear the code in the engine compartment with the jumper and actually every time on startup ithe check light goes off but as soon as I exceed the 1700 rpm level or so then b oom the check light comes back on. I do not have a hand held to do it from inside the cab but think I can follow your instructions. Later I will post the results .
Thank you for your patience and sharing your experience. This is a kind and helpful forum and I have learned a lot by changing out the headgaskets and the upper idler pulley the source of an otherwise difficult leak to find. Kept thinking it was comin g from behind the water pump. the timing cover hides a lot of what I needed to observe. I really think the upper ider sealant leak is what caused the overheating and ultimately lead to blown head gaskets. Have a good day in your toy! Mine is getting the recall on the relay rod. Will drive it home tonight and try the test.

Dave Mooney

I have located a used knock sensor for $10 from Engine Rebuilders' supply in Portland, Oregon. I will try Mudcat's idea of installing a "false" knock sensor to my driver's side engine mount. Has anyone else tried this shortcut rather than tearing down an otherwise great running 3.0 VZE engine after doing their own personal head gasket repair? Dealer price for new wire is $9.75.
Do I need to do any additional grounding? How can I verify the "used" knock sensor is electrically sound? Curious. I couldn't locate in the factory service manual. I'll look in Volume 2 when I get home under electrical systems 94 4Runner. I want to get the TPS, idle , timing, to spec. Currently running the engine timing advanced(clockwise from 10 degres btdc) and an increase in power and acceleration is noted.

Randle Tays

i have a 96 TACOMA 4X4 3.4 v6 265 75 15 with magnaflow exhaust and spectra cold air intake and its overheating and i just replace thermostat waterpump head gasket and know its missing really bad

95slowrunnerr

Ok so a couple weeks ago I didnt realize my 4runner was running without coolant so it overheated. I had someone bring me antifreeze. when i got home it started leaking from the valve cover gasket. so i replaced it. 2 days later I the check engine light came on and i got a code 52 which is the knock sensor. I didnt hear a knock and my vehicle was lacking power so i new it was a bad sensor. when i took off the intake the plug between the harness and the sensor was shaved so i replaced that as well. when i put everything back it was running fine quick response no lack of power but i still had the code 52 even after i reset it. now i dont know what it could be i dont hear a knock so i dont think its anything major. if you can help that would be awesome.

Kristin Walker

I bought my 1991 4 runner about a year ago and it had the code 52 for my knock sensor, its always had a power issue but after having to use my emergency flashers to pull over so traffic can pass me I had had enough. I wasn't able to go more than 30 mph. It just drains the crap out of your truck not to mention the really crappy gas mileage that comes with it. This is the first time I have done anything like this but with a great write up I found through the forum, my manual and a little help from a friend Its almost done.