Use this link to the oneline http://jagrepair.com/images/AutoRepa.../jagxk2003.pdf and go to fig 4.1 and you will see the information on the Knock Sensor. All leads go into the engine control module so you will need to know the color code on the wire. From what I can see the connection is at location EMS9

 

Hi Graham

The owner of this Jaguar garage was pretty knowledgeable about these 20 inch BBS wheels causing more stress on the suspension parts than stock wheels. They seem it ride a lot harder than my old XK8 with the 18" wheels. According to him, my XKR was not the first one that showed this kind of suspension ware. I only have 52k miles on my Jag and I know it was not abused by the previous owners.

Bill N

 

I highly doubt the wiring in your center console would have any influence on the knock sensor common ground. Switching sides sure would have told you if it were a sensor or the wiring... i would've tried it considering the cost ya paid. Oh well, hindsight and all that, try not to think about it. Now, enjoy your ramen noodles for the next few months...ahhh, memories of college.

 

Hi Gus

It looks like they tied Pl26 pin2 (white wire) to Pl27 pin2 (white wire) they are both common at the EMS9 junction. If pin2 on Pl26 read high at this plug with the knock sensor not connected, then I would assume that the problem is between Pl26 pin2 to either Pl1 pin18 or from Pl1 pin18 to the common connection at EMS9. All I have to do is find out where Pl1 and the EMS9 connection is located. Any ideas on how to find these locations would be really helpful.

Thanks for you help. I had printed out this page a few weeks ago to help find the knock sensor electrical hookup for this problem. I should have pursued it more then. But as I said in my thread everyone assumed it was the actual knock sensor that was heat sensitive.

Bill N

 

Matt

I got some good info from Gus regarding the wiring schematic. Hind site is right, I have been retired to long and forgot all my College electronic engineering courses. I should be able to find the problem and fix it once I locate the connectors. The Service manager could have spliced the wires and not told me, but he is to honest and his garage has a really good reputation. We all just assumed to much. I will talk to him tomorrow about giving me some credit on my next bill for future repairs that I will need. I think that is fair.

Bill N

 

Go to the beginning of the oneline and it should give you a guide on identifying the location. From what I could see it should be in the location of the Engine Control Module (EM).

 

Outch!

Glad you got it sorted though!. I also think that was a pretty reasonable price for all that work.

One question - had you noticed any problems with the handling or ride (or improvements afterwards) with all the suspension work?

When I first got my car I thought the handling was a little 'squirly' on rough roads, but a set of new tires (Michelin) seemed to improve it a lot. Still gives me scuttle shake if I hit a bad patch while cornering though...

-Steve

 

Steve

Just got home from Motorcars and the car seemed to drive better. I checked all the parts that were replaced and some looked OK to me, but they were replaced in pairs, so one bad --one OK. If you read through all the threads, you can see the history of the problem.

I could have saved a few bucks if I had ohm ed out the knock sensors and cables, but they found a few gasket problems when they removed the supercharger, so all was not in vain. It is nice not to have the RP message show up anymore.

I have the 20" rims on mine and the ride is harsher than the standard wheels. They found one of the shocks that should be replaced soon. Dean suggested that I put a set of Blistens on the front. He said I would get a smoother ride with them. The total parts cost was $900 and labor was $1120. Add 4 wheel alignment and State tax and it came up to $2250.

I am still looking for the junction where these wires for the knock sensor connect at EMS9. I can see it on the schematic but I can not find where it is located on the car.

Bill N

 

It looks like the junction at EMS9 is a floating ground for the shielded wires that hook up there, but I physically can't find it's location. Anybody know where it could be???

Bill N

 

According to the diagram, EMS9 is a splice located inside the harness between the connector to the ECM (EM80) and the 57 pin connector (PI1, Engine Harness to Engine Management Harness).

 

I would say at or near the ECM otherwise it would not have the prefix ECM.

 

Paul

Thanks for the help. I would assume the only way to fully correct the problem is to get a new harness or just go along the the repair the garage made by slicing the two floating ground wires together at the knock sensors. My only concern is what caused the problem in the harness?

Bill N

 

A very complex harness, certainly not worth changing. The jumper method that they used is (in my opinion) perfectly acceptable, but probably should be documented for future reference.

 

Paul

I have documented the electrical changes for my records. I have compiled as much service history as I could find for the car dating back to when it was shipped to the USA. Since I have owned the car, about six months, a lot of work was done. I was able to get the first $2400 paid by the extended warranty the second owner bought. This $2250 service I paid for, so there is close to $5000 spent on repairs during the six month period. I still have about $1500 in future repairs that I want to do, which should make the car reliable for another 10 years. Then all I have to do is drive and enjoy it. Who ever buys the Jag from me, when I get to old to drive, will get a really nice Classic XKR Jaguar fully documented. Hopefully it will be someone on our Forum. Thanks for all your help.

Bill N