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PIG153L ground stud is the upstream sensors return wire shields as the wires goes to the ECU
The ECU also has a dedicated external case ground strap
The ECU also has wires from the inside the ECU connector to car frame ground
Researching ground stud locations
I use to use a part referred to as a bottle rocket to make the connection of the stripped back exposed shield to the ground studs as a short pigtail / wire lead
See page 28 bottom right corner for ground stud PIG153L and PIG153R location
This would be on the engine rear firewall , left and right as there are 2 on opposite sides of the car
These 2 ground studs will cover both the shield grounds and the ground wires out of the ECU connectors
Well, with the different error codes, I think it is a bad O2 sensor. At least I know it is not a bad coil wire since it is a different code and the fact that it did not start off with a check engine light. I drove it about 100mph before I got it.
I do believe you are chasing the incorrect diagnosis with the O2 sensors.
DTC code P1313 & P1314 refers to "catalyst damage misfire cylinders 1,2 & 3 (P1313) whilst P1314 refers to cylinders 4,5, & 6.
Possible causes refer you to DTC P0300, random misfire detected, and a long list of possible causes are listed,
This list does not include O2 sensors.
I have attached page 16 (P1313 & P1314) and page 7 (P0300) from the complete summary.
Might I suggest you get hold of a full copy for future reference.
John raises excellent points. Don't discount any of the possible causes of P0300. P1313 and P1314 just mean the misfires are so consistent that catalyst damage will occur. The root cause is misfires. In my experience, the GEMS EMS is not good at identifying specific cylinder misfires, unfortunately
Did you find any damaged insulation on the coil wiring?
Is it possible your fuel has become contaminated with water?
Is it possible that one or more of the CKPS electrical connector pins has partially backed out of the connector? This is a common issue, especially with aftermarket CKPS's.
Is the vacuum line connected to the fuel pressure regulator, and if so, if you disconnect the vacuum hose do you see wet fuel in the vacuum fitting? This would mean the diaphragm has ruptured, which allows raw unmetered fuel to be inhaled into the air intake, and also leads to low fuel pressure...If you don't see wet fuel at the vacuum hose fitting, crank the engine briefly then check again.
Are the misfire codes the only ones triggered, or are there any others that could be helpful clues? There are potential causes of misfires that are not on the DTC Summary but they will usually trigger additional codes for things like fuel injectors, ignition coils, lean running, timing, CMPS, etc. Any other clues at all could be helpful.
Thanks for ALL of the information and it looks like I have some more work to do. I do not have any other codes. So I guess I am going to start with the coil wires and move to vacuum lines after I figure out where you are referring to. I just thought since I had 1313 and then 1314 that I had it. I put back in the old O2 just to make sure.
since I bought the car I have not even gone through all the gas that was in the car so water still could be a possibility. Could not hurt to put a can of sea foam in.
since I bought the car I have not even gone through all the gas that was in the car so water still could be a possibility. Could not hurt to put a can of sea foam in.
I haven't used the Seafoam fuel tank additive, but I have had excellent results from the Heet fuel system dryer products. When I suspect water contamination, I add two of the red bottles of Heet to the fuel tank and drive the car over a bumpy section of road to help agitate the fuel tank and mix the Heet with any water that may be in the tank. Things will usually improve quickly.
You can test the fuel for contamination by collecting some in a clear container and allowing it to decant for 30 minutes or more. If there is water in the fuel, you will see a line develop between the water at the bottom and the less dense gasoline floating on top. A relatively convenient way to collect some fuel is to disconnect the fuel line from the fuel rail, aim it into a catch container (you may need to slip a longer piece of rubber hose over it to be able to aim it into the catch container - I use about 4 to 6 feet 5/8 inch I.D. heater hose aimed into an empty container sitting on the ground. Turn the key to position II (Ignition ON) and let the fuel pump run for its priming cycle of a few seconds. Repeat until you have about a quart of fuel in your catch container. If your catch container is not transparent, pour your collected fuel into a clear glass or plastic container and allow it to sit somewhere where it won't be bumped. Usually you will see the separation line begin to form within 30 minutes or so.
Ok checking the water. Kind of hope there is water in it. Also here is a picture of my coil wires. Surprisingly they look brand new so I don’t think that is it.
Ok checking the water. Kind of hope there is water in it. Also here is a picture of my coil wires. Surprisingly they look brand new so I don’t think that is it.
Check every wire carefully, and especially check at the rear of the head where the harness bends - that is a common point where problems occur. But do your water check first. It could be that simple.
Your # 6 coil wire looks more Light Green / Orange than Purple
# 6 should be Purple
# 5 should be Orange
On M' Lady Penelope the same legth of 1/4 inch hose ( cheap by the foot at hardware store ) can be stuffed down the fuel filler and in theory pulls from the bottom of the fuel tank where water would be and not the fuel pump pickup which should be higher
On some X300's from reading others they have a anti - siphon trap (different then the no - lead nozzle door ) to prevent this
Yeah, five is orange, and six is purple. I changed the #4 coil and drove it about 60 miles. So far, so good. I think I will check the wires in the rear because I drove it without the coil cover, and maybe it was pinching. I will let you know tomorrow when I pull back the tape.
Now that I have everything completed, I need to drive it to see if the codes are gone and also drive it to follow the conditions to get past emission. Luckily, I have a Jag that is the same color and year so I can move my only plate back and forth, hoping that a cop is not a Jag fan that knows the difference between an XK8 and an XJ6L
You can puchase a 5 dollor high temp ( crack pipe ) lighter at the discount cigarette stores
On car you can measure the DC volts on the return wire as I think it is around 3.5 volts , but you can compare to another
They are feed 5.0 volts from the ECU
There is a shielded wire ground terminal on the rear engine firewall that protects all 4 return signals wires
Dedicated ground strap on the ECU case mount bolt ?
O2 sensors ( 4 ) heater fuse ( 1 ) so they will read correctly ? one fuse for all 4 either # 10 . 12 . 14 , or 16 right engine bay fuse box
These 4 fuses require the relay in the corner of the fuse box to close and can have a burnt / compromised power contacts inside
Swap relay with the left engine bay fuse box relay
so I went to test the O2 sensors following this procedure and I think they failed just on the first step. Of course we don’t have two white wires so I am assuming that the red and white are the two that I needed to test for the heating sensor because it was the only wire that produced ohms. I tested two and they both only came to 5.4 ohms instead of the 10 that he suggested in the video. Anyone have any comments on this. Are they crap
02-23-2024, 02:00 PM
