Knock Sensor issues (1 Viewer)

[jsix321]

After getting a knock sensor code I decided to change both out and fix the hack wiring the PO did on the connectors. I order 2 new Denso knock sensors and new pigtails to repair the wiring. The Existing wires were spliced in one spot and hand twisted with a piece of electrical tape in another. I started at the hand twist area and removed the wire to the knock sensor. I took a new pigtail apart, pic below, and used one of those connectors with solder in them to reconnect followed by heat shrink. I then replaced the sensors and plugged them in.

The problem I’m getting now is the code P0325 is back and now the truck idles really low and has no power. Is this from the replacement, did I mess something else up? Not sure what’s going on and looking for some help on this issue.

Thanks in advance and below are pictures of the install.

 

[jsix321]

Also while I was in there, I noticed a wire that came out of the same loom for the knock sensor wire wasn’t hooked up to anything. I believe it goes to the temp sensor for the guage, can someone confirm? The below picture is one I found online and the sensor labeled ECT (for gauge) doesn’t have anything hooked to it and it looks like that wire should go to it. It’s also a hack wiring job as well.

 

[saraujo]

I ordered 2 Knock sensors from Ebay as well, no issues with them (knock <{no pun intended}> on wood).

Did you test the sensor for continuity with a meter? I did test mine before I installed them.

Testing video just found -->

 

[saraujo]

Any progress on this? Hope this helped!

 

[jsix321]

No real progress yet. I jacket the rig back up, pulled the tire off for access and got side tracker with other issues. The temp sensor that feeds the ECU had one of the wires broken right at the pigtail, and the other wire was barely connected. This was probably my fault from bumping them while changing the knock sensors. The other temp sensor that feeds the dash guage wasn’t connected and the pigtail connector was not on the end of the wire, I guess the PO just stripped the wire and pushed it into the connector. Also started thinking about the brittle cracked vacuum lines that go to the charcoal canister and that I might have bumped them replacing the knock sensors.

I figured while I’m here I might as well address all of this. My thoughts were to hook everything back up to make sure it all works right and order what’s needed to make the proper repairs.

1) For the temp sensor that feeds the dash gauge, I crimped on a small connector and pushed it back in the back of the sensor.

2). For the temp sensor that feeds the ECU, I cut the old pigtail off and crimped a really small connector on each wire and plugged them back into the sensor. This was a super pain as I had to do this by feel, couldn’t see what I was doing. My method was feel the sensor and push the connectors on, then take a picture with my phone held under the intake to verify I did right.

3). For the knock sensors, I pulled the number one sensor and replaced it with the original one that wasn’t originally throwing a code.

4). Installed new vacuum lines on the charcoal canister just in case I bumped one of those and opened up a crack.

After getting all this done I put the wheel back on and fired it up. It started perfectly and idled perfectly. I cleared the codes and took it for a drive. The dash temp gauge is working and my scan gauge temp is working good again. It drive good but still feels like I’m down on power.

I did finally get a code of PO330 which is the number 2 knock sensor, but no other problems. What this tells me is I need to get knock sensors that work and new connectors for the two temp sensors. I went ahead and ordered the 2 new pigtail connectors, OEM knock sensors and a vacuum line kit.

As of now I’m in stand by waiting on parts. I’ll probably put a few miles on it while I’m waiting, but don’t feel real comfortable with it until I get real connectors on the sensors. Also I’m hoping that when I change out those old vacuum lines with new ones I’ll get some of the performance back. I’m hoping some are cracked that’s part of the problem.

 

[jsix321]

Any progress on this? Hope this helped!

That video did help, I’ll be checking the Denso ones I got off eBay to see how they test.

 

[jsix321]

On a positive note, my lift kit came in. May get a wild hair while I’m waiting on parts and install it.

 

[saraujo]

No real progress yet. I jacket the rig back up, pulled the tire off for access and got side tracker with other issues. The temp sensor that feeds the ECU had one of the wires broken right at the pigtail, and the other wire was barely connected. This was probably my fault from bumping them while changing the knock sensors. The other temp sensor that feeds the dash guage wasn’t connected and the pigtail connector was not on the end of the wire, I guess the PO just stripped the wire and pushed it into the connector. Also started thinking about the brittle cracked vacuum lines that go to the charcoal canister and that I might have bumped them replacing the knock sensors.

I figured while I’m here I might as well address all of this. My thoughts were to hook everything back up to make sure it all works right and order what’s needed to make the proper repairs.

1) For the temp sensor that feeds the dash gauge, I crimped on a small connector and pushed it back in the back of the sensor.

2). For the temp sensor that feeds the ECU, I cut the old pigtail off and crimped a really small connector on each wire and plugged them back into the sensor. This was a super pain as I had to do this by feel, couldn’t see what I was doing. My method was feel the sensor and push the connectors on, then take a picture with my phone held under the intake to verify I did right.

3). For the knock sensors, I pulled the number one sensor and replaced it with the original one that wasn’t originally throwing a code.

4). Installed new vacuum lines on the charcoal canister just in case I bumped one of those and opened up a crack.

After getting all this done I put the wheel back on and fired it up. It started perfectly and idled perfectly. I cleared the codes and took it for a drive. The dash temp gauge is working and my scan gauge temp is working good again. It drive good but still feels like I’m down on power.

I did finally get a code of PO330 which is the number 2 knock sensor, but no other problems. What this tells me is I need to get knock sensors that work and new connectors for the two temp sensors. I went ahead and ordered the 2 new pigtail connectors, OEM knock sensors and a vacuum line kit.

As of now I’m in stand by waiting on parts. I’ll probably put a few miles on it while I’m waiting, but don’t feel real comfortable with it until I get real connectors on the sensors. Also I’m hoping that when I change out those old vacuum lines with new ones I’ll get some of the performance back. I’m hoping some are cracked that’s part of the problem.

FWIW - When I had the knock sensor issues, just a couple of months ago, I def felt that 'down on power' issue as well. Once replaced, got the power back.

I ordered vacuum line set from Wits End and I'm replacing as I go along, so that's a great idea for you to have ordered.

Let us know how those parts and the lift kit goes!

 

[jsix321]

Installed the lift kit this past weekend, was way easier than I thought it would be. Also got some Yokohama 315's installed today.

 

[jsix321]

Got it all fixed up this morning. Installed another OEM knock sensor, proper connectors and cleaned up wiring to both temp sensors. Works great and no more knock sensor codes. Funny thing is it runs a lot better now. I guess when it throws a knock sensor code, it retards the timing or something and doesn’t run good. All good now!!

 

[saraujo]

Great job! Yep, those knock sensors will definitely disrupt the timing, causing power retardation. Now time to get out and explore!

BTW - what kind of rear bumper do you have installed? A buddy of mine has a 97' LX450 and I'd love to get one too, but time and resources will tell if that's ever possible.

 

[jsix321]

Great job! Yep, those knock sensors will definitely disrupt the timing, causing power retardation. Now time to get out and explore!

BTW - what kind of rear bumper do you have installed? A buddy of mine has a 97' LX450 and I'd love to get one too, but time and resources will tell if that's ever possible.

Thanks and working through it all slowly.

It still has the factory rear bumper on it now. Going to get in on the 4x4labs group buy and get a kit for their dual rear swing out and sliders. I’ll put them together myself and have them powder coated locally to save money.