Knock sensor. Replace one or both?
- Thread starter LuckyOreo
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x2 The knock sensors are basically microphones. So unless the other one is deaf etc, no need to replace it. There are aftermarket ones quite a bit cheaper than OEM. You would need to search mud to find the thread.
cheers,
george.
cheers,
george.
O' Reillys on right...much cheaper
I purchased x2 from this seller on Ebay earlier this year and they tested just fine and working great!
Hope this helps
Toyota Land Cruiser Lexus GS400 LS400 SC400 LS430 LX450 LX470 Knock Sensor OEM | eBay
Find many great new & used options and get the best deals for Toyota Land Cruiser Lexus GS400 LS400 SC400 LS430 LX450 LX470 Knock Sensor OEM at the best online prices at eBay! Free shipping for many products!
www.ebay.com
Hope this helps
^ precision markup more likely 
cheers,
george.
cheers,
george.
Just finished getting rid of CEL 52 and 55. Bit of a marathon. I'd recommend you view the wiring with suspicion. I started by trying the $30 specials and still both error codes. (BTW with enough practice it is not really too bad to get in there with a 10-12 inch extension on the ratchet to remove them. It was harder getting the plugs off actually. Not a lot of room and my fingers were not really strong enough for Mr. Toyota's locking connectors. I had to use really long pliers.
I found an old set of sensors on the shelf whose provenance I could not recall, so I thought I would try them while waiting for another set from the OEM/used supplier Saraujo recommended above. The connector for the rear sensor fell off the wire during this process. Fortunately I had bough a little harness with two knock sensor plugs from Amazon so I was able to splice in a new connector.
Amazon product
After I spliced in the new connector error code 55 went away. No joy on the front knock sensor.
The connector on the front sensor looked new-ish. So I kind of ignored it and assumed that the engine control unit is just sensitive and I would need to buy a new OEM expensive one. But coincidentally the OEM/used sensors from the ebay seller showed up in the mail today, so I decided to try swapping one of those in. CEL code 52 persisted. I had bought 2 of the OEM/used so I tried the other one too. Still no joy. I looked at the front connector again and it still looked good, but cheap--and I had the second connector from the little harness at hand so I decided to splice in the new connector and lo and behold NO CEL! Moral of the story is ... maybe its the wiring...
I found an old set of sensors on the shelf whose provenance I could not recall, so I thought I would try them while waiting for another set from the OEM/used supplier Saraujo recommended above. The connector for the rear sensor fell off the wire during this process. Fortunately I had bough a little harness with two knock sensor plugs from Amazon so I was able to splice in a new connector.
Amazon product
After I spliced in the new connector error code 55 went away. No joy on the front knock sensor.
The connector on the front sensor looked new-ish. So I kind of ignored it and assumed that the engine control unit is just sensitive and I would need to buy a new OEM expensive one. But coincidentally the OEM/used sensors from the ebay seller showed up in the mail today, so I decided to try swapping one of those in. CEL code 52 persisted. I had bought 2 of the OEM/used so I tried the other one too. Still no joy. I looked at the front connector again and it still looked good, but cheap--and I had the second connector from the little harness at hand so I decided to splice in the new connector and lo and behold NO CEL! Moral of the story is ... maybe its the wiring...
@John Young - Really glad you found out it was ultimately the connectors. Mine fell off too, so had to replace them as well. But my Knock Sensors were also bad and the ones I recommended worked great. I hope you were able to test the Ebay ones you just received with a multimeter and perhaps even install them, if needed. But if you didnt need them and they tested fine on the multimeter, then you have yourself some future spares.
Well... I'm not actually sure. The sensors also could have been bad. It is much too much trouble to try to figure it out now.@John Young - Really glad you found out it was ultimately the connectors. Mine fell off too, so had to replace them as well. But my Knock Sensors were also bad and the ones I recommended worked great. I hope you were able to test the Ebay ones you just received with a multimeter and perhaps even install them, if needed. But if you didnt need them and they tested fine on the multimeter, then you have yourself some future spares.
My truck is now close to 30 years old and spent most of that time in the desert. I'm gradually replacing electrical stuff that looks bad... like the plug goes to the alternator.
It worked fine, surprisingly. I just really did not like the look of it so it had to go. With all this fiddling, a wire broke off the coolant temperature SENSOR and I replaced that today. I've also ordered a new plug for the coolant temperature sensor. The plastic bits under the hood seem to be getting pretty brittle.
Yep, understood. Everything you're explaining, the same happened while I was diagnosing the knock sensors and I also had to replace my coolant temp sensor connector, both knock sensor connectors and both knock sensors. Oh the joys of the cost, but the beauty of where these rigs take us is irreplaceable.
Take care John!
- Thread starter
- #12
So I ordered from orileys and it's not the same part. They must have found a different supplier.
This is what I recieved
Yep, doesn't look like what @woodsman 44 purchased in comment#4 of this thread, completely different part#'s as far as I can tell. Did your knock sensors fail again?
Thanks for posting that up. I'm replacing my knock sensor wiring chasing down an issue. It looks like the link you provided isn't plug and play for FZJ80's, but we can cut the ends off and splice them in. Is that correct?
I broke one of my sensors doing a head gasket, the aftermarket sensor from eBay has worked just fine at a fraction of the cost. I also had to repair my wiring, and the terminal can be unclipped from the connector if the wire isn't damaged. I wouldn't cut and splice unless I had to.
I respectfully disagree with you. Those connectors are all 25 years old and have been soaking in engine heat for all that time. A good splice is not too hard to do. I soldered and used heat shrink tubing. I'd suggest that replacing the connectors is just good preventative maintenance if they are damaged in any way--which they invariably seem to be.
Yes; that is what I did. Much cheaper and easier to get than the exact right part. It is an identical connector but it is for a pigtail for another vehicle.
Right. But the wire can be removed from the old connector housing by removing a plastic pin. It then snaps into the new connector. Unless the wire is already damaged, there is no need to cut and splice.
