I just got a CEL knock sensor error. Where do I locate these in the engine?
Knock sensor. Replace one or both? (3 Viewers)
- Thread starter LuckyOreo
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There are two, one toward the front of the block, the other near the rear.
Has anyone been doing any work up under there recently?
Look through the thread below, Knock sensor #1 is above and to the right of the oil filter. Knock sensor #2 is above the starter and has to be approached from the left front wheel well (unless you have a lift).
forum.ih8mud.com
Looking down on the block from above, left side (red arrows):
This shows the #2 knock sensor (red arrow, with a broken connector) looking up from the left wheel well:
forum.ih8mud.com
Has anyone been doing any work up under there recently?
Look through the thread below, Knock sensor #1 is above and to the right of the oil filter. Knock sensor #2 is above the starter and has to be approached from the left front wheel well (unless you have a lift).
1FZ-FE block/head sending units???
1995 80 series I am stuck trying to figure out what all the sensors are on the block and head. I have a guy rebuilding the engine for me and I want to replace all the sensors but I have no idea what they are or what they are called. Any help for this noob would be greatly appreciated!
forum.ih8mud.com
Looking down on the block from above, left side (red arrows):
This shows the #2 knock sensor (red arrow, with a broken connector) looking up from the left wheel well:
Another busted Knock sensor connector
Recently found the #2 Knock sensor connector to have snapped off, the connector was just loosely hanging on the knock sensor, the tip off was an intermiitent loss of power. So the sensor connector piece was stuck inside the harness connector and after a few tries was unable to remove the stuck...
forum.ih8mud.com
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There are good diagrams in the Field Service Manual for the 80 (see Resources tab at the top of the page). But generally, locate the oil filter on the drivers side of the engine and one sensor is pretty visible up and to the left of it. The other is harder to see but if you bend down and peer towards the rear of the engine you can see it. The CEL codes using the paperclip reading method (search youtube) (assuming you have OBD1 on your 80) will tell you front or rear or both. Personally, I found it annoying enough of a job that I would do both at the same time. If your CEL code says one is good, keep that as a field expedient spare. Don't cheap out too much on these either. I had good success with genuine but used sensors from Ebay. Even so, it took several tries and at the end of it all I ended up replacing both pigtail connectors as mine were in bad, bad shape. Mine is a Middle East truck so it has spent a lot of time in the heat and a lot of the connectors under the hood are getting to the point where if I am fiddling with something I most always just replace the connector. You can find cheaper connectors for other toyotas on Amazon. You might want to look at my posts here. And an additional note: after a while I figured out that I did not have to reach through the wheel well and could, with the right extensions reach both from above.
Unfortunately a lot of the information is scattered in several threads. Keep searching and reading and you will find the info you need.
The front one my 80 threw the code, when I reached in the connector came loose in my hand. Then removed the sensor (see pic below) it was beyond done with corrosion. I had to replace the sensor and the wire/connector with it. Removing the oil filter does make a huge difference to get to it, and I also removed the charcoal cannister and it's bracket. With that extra room it was simple to connect the new connector to the old wire and put it back together. The connector on mine disintegrated when I removed it, and it was really helpful to have extra wire with the new connector.
Connector: Amazon product ASIN B01N3N5PHA
Sensor: Amazon product ASIN B016S1GK3K
More room to use hand tools with oil filter out. The sensor is the one at the "1-oh clock" position from the oil filter.
Connector: Amazon product ASIN B01N3N5PHA
Sensor: Amazon product ASIN B016S1GK3K
More room to use hand tools with oil filter out. The sensor is the one at the "1-oh clock" position from the oil filter.
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Very Helpful.
My error is sensor 1
It the one next to the oil filter sensor 1 or 2?
My error is sensor 1
It the one next to the oil filter sensor 1 or 2?
sensor 1 is towards the front of the engine near oil filter.
very cool.
Thank you
Thank you
Replaced the knock sensor per instruction on this thread with Amazon parts from these thread. worked great.
The wire snapped off so I was happy I got the harness and sensor together and just crimped the new harness to the red wire that came out of the harness.
It was pretty short wire left so there is not much room for a mistake.
The wire snapped off so I was happy I got the harness and sensor together and just crimped the new harness to the red wire that came out of the harness.
It was pretty short wire left so there is not much room for a mistake.
Gonna see if I can revive this thread before starting (yet) another Code 52 thread.
'94 FZJ80. Recent HG job done. Mechanic replaced knock sensor #1 while doing the job, but was waiting on the part for KS#2, and I needed the truck back. Was (and is) throwing code 52.
Plan was to bring the truck back to the mechanic in a few days once he had the part and have him throw the second sensor on; however, he got super busy and wasn't really responding, so I ordered the part (OEM) from Amayama and just knocked (see what I did there?) it out myself in about 10 minutes. Easiest job I've ever done on this truck, honestly.
I should mention that the truck has run smooth and strong since the HG job, and still is...
Alas, code 52 persists! I went back in to check the connections and wiring, and while doing so, the connector to the ECT (gauge) sensor came off and it was obviously damaged, with the connector on the sensor itself crumbling away. (Took me FOREVER to figure out which sensor that was, finally stumbled upon a MUD thread that had them labeled (Thanks, @flintknapper , Temp sensor part number - https://forum.ih8mud.com/threads/temp-sensor-part-number.1254586/#post-14863089)
To my untrained eye (and without actually removing the wiring harness), it appears that the wire/connector for the ECT (gauge) sensor is a pigtail off of the wires with the knock sensors. Is that correct? And if so, would a bad connection to the ECT sensor potentially cause the code 52? (Since I've read that Code 52 is for lack of signal from the knock sensors to the ECU, and most often a wiring issue).
Thoughts? I'm replacing the ECT sensor and it's wire-side connector regardless, but I would love it if it might also solve my code 52 issue.
'94 FZJ80. Recent HG job done. Mechanic replaced knock sensor #1 while doing the job, but was waiting on the part for KS#2, and I needed the truck back. Was (and is) throwing code 52.
Plan was to bring the truck back to the mechanic in a few days once he had the part and have him throw the second sensor on; however, he got super busy and wasn't really responding, so I ordered the part (OEM) from Amayama and just knocked (see what I did there?) it out myself in about 10 minutes. Easiest job I've ever done on this truck, honestly.
I should mention that the truck has run smooth and strong since the HG job, and still is...
Alas, code 52 persists! I went back in to check the connections and wiring, and while doing so, the connector to the ECT (gauge) sensor came off and it was obviously damaged, with the connector on the sensor itself crumbling away. (Took me FOREVER to figure out which sensor that was, finally stumbled upon a MUD thread that had them labeled (Thanks, @flintknapper , Temp sensor part number - https://forum.ih8mud.com/threads/temp-sensor-part-number.1254586/#post-14863089)
To my untrained eye (and without actually removing the wiring harness), it appears that the wire/connector for the ECT (gauge) sensor is a pigtail off of the wires with the knock sensors. Is that correct? And if so, would a bad connection to the ECT sensor potentially cause the code 52? (Since I've read that Code 52 is for lack of signal from the knock sensors to the ECU, and most often a wiring issue).
Thoughts? I'm replacing the ECT sensor and it's wire-side connector regardless, but I would love it if it might also solve my code 52 issue.
Code 52 is KS for sure. I've replaced both of my KS and pigtails. Getr' done.
Make sure and save this for future. I have a 93', so we're same-same.
Make sure and save this for future. I have a 93', so we're same-same.
Hey fellow h8tr’s. On my 91 Cruiser, after 10 years of no problems, I was stranded on the side of the road after a large engine miss. The hand brake light, engine light and AT temp lights all stayed on. The truck would not start while on the side of the road.
I got it home and the dang truck fired back up. Nothing seems a miss. I jumped the OBD1 and got code 12. Which says “Knock Sensor Signal” but I also see RPM signal in the post above. Is there a knock sensor on a 3FE?
Could this be the cause as to why the truck shut off and wouldn’t re start?
I got it home and the dang truck fired back up. Nothing seems a miss. I jumped the OBD1 and got code 12. Which says “Knock Sensor Signal” but I also see RPM signal in the post above. Is there a knock sensor on a 3FE?
Could this be the cause as to why the truck shut off and wouldn’t re start?
My experience with the 1FZ-FE was that the bad knock sensors definitely caused terrible running. But I did not get the 80 running well until I fixed the wiring going to the mass air sensor. For some reason those wires and connectors seem failure-prone. I don't know if the 3FE has the mass air sensor but if it does I would take a close look at that too. Re replacing the knock sensors, at least on the 1FE-FZ they are enough of a challenge to change that I would suggest using the expensive OEM and doing both at one time and ALSO getting new connectors for the wiring harness. At lease my 93 had really bad and worn out plastic connector housings.
Ok good call! I’ll take a look at that too. Thanks!
