So my jag has an open circuit reading in Cylinder 3. I've taken the manifold cover off and exposed the loom however it all looks good with no wear marks on number 3. Previous to this I moved the coil packs and switched them round just in case it was a failing coil pack and the fault never moved, still in number 3.
Now I am assuming that number 3 is the middle pack closest to the bulkhead on my 2002 petrol xtype. I have checked all 3 closest to the bulkhead just in case.
So I am wondering if I switch on the ignition with the battey connected and test the circuits for voltage then I should get 12v coming in ? Could someone tell me what all the coloured witing is. I am assuming the black wire is the negative and the red is the positive.
Have I missed anything?

 

you are correct.
Could you post the code are you sure its not for the injector.

 

Lubino, if you look at #3 cylinder, the wires to the coil are as follows:

Red/white wire is your battery power
Black is your ground wire
Yellow/green is a common wire to cylinders 1/3/5 coming from the ECU
Green/purple is a wire coming from the ECU.

With all this being said, checking the black wire is easy as you can simply do a continuity check from the plug end at the coil to chassis ground. You should get under 5 ohms. Anything higher and you have an issue.

As for the red/white wire, I would measure this with the plug made up. You can slide a paperclip into the back side of the plug and measure the voltage at the pin this way. I say to do it this way as I have seen issues where a wire develops a high resistance due to getting water inside the insulation and you will see a good voltage when there is no load, but when you start passing current, the voltage drops significantly. You should be getting over 12.0 VDC with the ignition on and the motor not running.

Making a logical leap, I would have to say that the yellow/green wire is good as you are not having issues with cylinders 1 and 5.

As for checking the green/purple wire, unfortunately, the only way that I can see checking this one is to remove the plug from the ECU and do a continuity check from one plug to the other. At the ECU plug, it will be pin 88. Again, if you are getting over 5 ohms of resistance, then that wire is bad and needs to be repaired.

 

Just put it all back together and codes 0171 0174 0303 1313 0203 1642 p1000
Just going onto my desktop.and will.wrote more in a second.

 

Thanks guys for all the help. Thermos, I got your message a tad late but I did check to se e if cylinder 3 was getting a power suppy.
I have replaced all the bits back in. Swapped the injector in number 3 from one I got from the scrappy (untested ofcourse). I am not sure if injectors have to be coded like in my td5.
I have checked all the hoses for the air and put jubilee clips on them to prevent unmetered air getting in.
The car is not going into limp mode
It drives pretty well except for a little resistance.
There is one thing I have done just before this all kicked off is to adjust the handbrake nut. Now I didnt take the wheels off and do it properly, just adjusted it until it felt good. I am wondering if this could cause the faults.

 

Incidentally, I connected the red and black wires to get the voltage so I imagine the earth is ok. I am wondering if it was possible I fitted a ropey injector, it misfires on heavy revs.

 

I am thinking it may be worth changing the oxygen sensors as these may be faulty hence causing the too lean fault. Which company do you lot use for spares online?

 

A big thank you to everyone who helped me on this thread. I tried another thing which was to use another code reader on the car. It erased all the code except the p1000 code. I am Hoping that this is the end of this problem. The rac code reader I was using was for some reason not allowing me to erase the codes etc.... Is this common?

 

Lubino, stick with a Bosch sensor. There are some funky sensors out there. If not Bosch, then atleast use another brand name that is common. Might cost you a little extra, but it will save you a lot of heart ache. You will also find that there are some cheapy O2 sensors out there that may seem like a good idea. For me (I work in the electrical world), they are. But, for the inexperienced electrical guy, it has you trying to match up wire colors and soldering wires to pins. Not impossible, but it can be very frustrating when you put in the new sensor and things are even more messed up than they were before.

On a side note, there are 2 types of O2 sensors used on the X-Type. If you look at the codes, you will see them refer to the sensors as say 1/1 or 2/1. The first number is simply telling you the side of the engine it is on (ie, 1 is for the side of the engine with the #1 cylinder; aka, bank 1; which would be the one against the firewall and 2 is saying that it is the side of the engine with Cylinder 2; aka, bank 2). The second number is telling you the type of sensor used. 1 is referring to the upstream sensor or the sensor nearest the engine. 2 is referring to the sensor beyond the catalytic converter, or the downstream sensor. The upstream sensor measures the fuel left in the exhaust system and the O2 level where the downstream sensor is sensing only O2 levels. So, make sure you get the correct sensor.

 

Thanks thermos for all the help. I will shortly be moving onto me next problem once all the cuts on my hands heal!

 

On a side note, you will want to get a specialty O2 sensor tool. Yes, they sell the socket style and atleast on my car, it was weak enough that it was expanding and slipping on the O2 sensor. You want the style that you have to put on the end of a breaker bar to atleast break it loose (you can use the socket style once it is loose). The type I am referring to is something like: Offset O2 Oxygen Sensor Socket Vacuum Switch 7 8 inch 22mm | eBay.

These work amazingly well and will help ensure you don't create a bigger issue. If you talk with your local auto parts store, they may even have a "free tool rental" program (common thing here in the US) where you can rent it and when you are done, they give you back all your money when you return the tool.