Toyogator00

Quick update...I’ve continued to research the best alternative aftermarket KS with the understanding that the OEM is discontinued for the 88 22RE. I found partsgeek.com which had what they claimed were original KS for my application. Even said “Denso” on the image. What was curious is that the same part number was listed for 88-94. I’m sure I saw a thread where it said you can’t mix ecu’s and KS between years. To double check, I called my Toyota dealer parts dept to check the part number and asked about what years it was applicable. They said 88-94 were all the same for the 22RE. To my surprise, he said he could get one which blows my mind since the same dept told me they were unavailable 2 weeks ago when I first started my code 52 journey. I’ll give it a shot and see if it works. If not, its back to wiring but I will feel better with an OEM part based on the threads I read on this site. Thanks again Gevo and Scope103 for trying to help.

Toyogator00

Code 52 Gone! (Fingers crossed). The OEM KS did the trick. When comparing the old KS to the new one I had a couple revelations. 1. I assumed all along and incorrectly that the KS in the 4runner was original. When comparing to the OEM it was clearly not. The OEM part had “Denso” printed on the side (Original OEM manufacturer). I don’t know how to describe it but it just felt better in the hand, better metal, etc. So the prior owner probably got a cheap aftermarket to fix his code 52. 2+ years later the part is bad and I’m working on it. 2. In hindsight, the old one didn’t look like it had been in a truck for 30 years. It had no markings or branding printed on it. So...here’s my conclusion.

We’ve seen the tech on this saying trouble shooting breaks down wiring 91% of the time, KS 8%, ECU 1%. I buy this 100% for the 3VZ based on my research. The location of the wire and harsh environment just makes sense. I’ve also seen a lot of disagreement on various threads regarding “testing” the old KS. Some say it needs special equipment and others say it can be tested by checking continuity between the signal pin and ground; and checking for voltage when tapping the block. Just for learning purposes I tried this with the old KS. Result...No continuity, and I got a small amount of voltage when the “knock” was simulated. But it was still bad, by evidence that the OEM replacement solved the code 52. So I’m a little dubious on the home bench test. Obviously if there’s continuity (internal workings shorted) or no voltage comes out with the knock simulation, we can determine its bad. But it will not tell you its good or good enough for the ECU to receive the signal.

For the 22RE...In hindsight, I spent a lot of time worrying about a shielded ground that I’m confident can be a real issue but never found tech for how to test this in the 22RE. I’m pretty sure wiring is not 91% of the issue for the 22RE as it likely is in the 3V3. It’d be interesting to know how often the shielding is the issue for both motors. This seems to be place everyone goes when nothing else has worked and they still get a code 52. a lot of the code 52 threads, including this one started 10 years ago. So, over time, it plausible that the KS itself could be an issue a higher percent of the time. Had I realized I had an aftermarket KS to begin with, I probably would have reversed my trouble shooting priorities. I should have felt good about the wiring after I had continuity between the ECU end of the wire and the KS end and moved on to studying the sensor. My unwavering faith in a 30 year old OEM part that wasn’t present, with 8% fail probability, cost of the sensor, inability to find and OEM replacement, and all the tech on the shielding biased me for sure. I hope this helps another 22RE owner with code 52.

Lastly, thanks again to all who contributed to this thread. I learned a lot, my sons learned a lot and it got the 4runner back on the road.

Gevo

Glad to see it resolved. I think code 52 'short...' is misleading... So far most of the code 52's on here have been KS replacement related not wiring. lol.