D2 Knock Sensor

HIDave

Well-known member
Sep 24, 2020
131
6
Hawaii
Aloha,

Recently had 02 sensors changed and the valve cover gaskets done. New plugs, wires and a belt also at the same time on our Disco 2.

After driving the truck for a bit, I would notice a puffing sound. Seemed to be coming from the bottom of the block. I went ahead and tightened all the bolts on the exhaust manifold. 2 of which we quite loose. Following that the puffing went away and the truck ran smooth.

After a bit more driving, the puffing came back. The code coming up is d2 on the ICarsoft reader. It is saying knock sensor lower. I clear the code the sound goes away and the truck runs smoothly again for a bit. Then the code and the puffing sound return after a short drive.

Any ideas would be helpful on what this may be. Bad Knock Sensor? Bad plugs?

Mahalo,
Dave
 

JohnB

Well-known member
Oct 18, 2007
2,292
12
Oregon
Is it the drivers knock sensor?
Reason I ask is the wire loom that runs to that knock sensor can get squished by the AC bracket if you're not careful when you assemble after doing valve cover gaskets.
 

HIDave

Well-known member
Sep 24, 2020
131
6
Hawaii
Is it the drivers knock sensor?
Reason I ask is the wire loom that runs to that knock sensor can get squished by the AC bracket if you're not careful when you assemble after doing valve cover gaskets.
Considering that I had to bring the truck back to the garage that did the valve cover gasket 3 times. Finally they did the job right but obviously in a hasty way this is very probable cause. Thank you. I'll check!
 

JohnB

Well-known member
Oct 18, 2007
2,292
12
Oregon
Well I only get to blame myself but managed to ruin mine and end up fixing a shielded wire.
 

HIDave

Well-known member
Sep 24, 2020
131
6
Hawaii
Well I only get to blame myself but managed to ruin mine and end up fixing a shielded wire.
Can you take a photo?

Otherwise, I think I am going to be stuck crawling round under the truck for hours searching for this.
 

HIDave

Well-known member
Sep 24, 2020
131
6
Hawaii
Would anyone be able to share with me the location of the lower Knock sensor?

Just spent over an hour looking at the schematic and laying under the truck, only to come back more lost than when I started?
 

JUKE179r

Well-known member
Sep 14, 2016
761
95
Suffolkshire, UK
There is 1 knock sensor on both sides of the engine block. The one on the LH side is right behind the engine mount near the oil dip stick. The RH side should be in a similar location.

 

mbrummal

Well-known member
Jan 23, 2009
2,893
22
Willow Spring, NC
Look at connectors C0626 and C0627 in the Electrical Library of the RAVE manual. It has pictures showing the sensors. Its pages 507-508 out of 705 on mine.
 

sdtim

Active member
Feb 21, 2021
31
11
Oceanside, CA
The knock sensor with the vulnerable wire is on the drivers side. I recently had an issue with mine that was triggering the three amigos. I had already replaced the sensors a few months prior.

I inspected & cleaned the connector at the sensor. Then wrapped the wire with a few layers of electrical tape. That seems to have resolved the issue.

You'll need to remove the plastic intake tube (1), belt cover (2) and AC compressor (3) (~10 mins worth of effort) to access the cable at the front and top of the engine. Don't forget to unplug the AC and Mass airflow sensor connectors before setting those pieces to the side.

knock sensor.jpg
knock sensor.jpg
 
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HIDave

Well-known member
Sep 24, 2020
131
6
Hawaii
The knock sensor with the vulnerable wire is on the drivers side. I recently had an issue with mine that was triggering the three amigos. I had already replaced the sensors a few months prior.

I inspected & cleaned the connector at the sensor. Then wrapped the wire with a few layers of electrical tape. That seems to have resolved the issue.

You'll need to remove the plastic intake tube (1), belt cover (2) and AC compressor (3) (~10 mins worth of effort) to access the cable at the front and top of the engine. Don't forget to unplug the AC and Mass airflow sensor connectors before setting those pieces to the side.

View attachment 61129
View attachment 61130
Tim,
This is terrific. Thank you so much for taking the images.

Mahalo,
David
 

jastutte

Well-known member
Nov 10, 2009
461
71
The knock sensor with the vulnerable wire is on the drivers side. I recently had an issue with mine that was triggering the three amigos. I had already replaced the sensors a few months prior.

I inspected & cleaned the connector at the sensor. Then wrapped the wire with a few layers of electrical tape. That seems to have resolved the issue.

You'll need to remove the plastic intake tube (1), belt cover (2) and AC compressor (3) (~10 mins worth of effort) to access the cable at the front and top of the engine. Don't forget to unplug the AC and Mass airflow sensor connectors before setting those pieces to the side.

View attachment 61129
View attachment 61130
how was the knock sensor issue triggering the three amigos?
 

sdtim

Active member
Feb 21, 2021
31
11
Oceanside, CA
how was the knock sensor issue triggering the three amigos?
I saw two error codes:
  • DTC knock sensor fault bank 1
  • P0327 knock/combustion vibration sensor A circuit low
They're probably different interpretations of the same error as I saw them listed in different modules on my code reader.