Well I changed the plugs and change all oxygen sensors. Now I am getting this. Did not get this till I took it on the road. The check engine light actually started blinking as I was pulling into the driveway. What did I do to cause this?

 

Hi Phil,

The first thing I would check are that the cylinder #5 and #6 coil wires were not switched - this is very easy to do on an X300.

Next I would check for cracked and missing insulation on the coil wires, especially at the rear end of the head where the harness takes a bend. You may have to carefully remove some of the harness covering to inspect the coil wires. When the insulation hardens and cracks and flakes away, the coil wires short together and lead to random misfires.

If you inadvertently switched any oxygen sensor connectors, I think you would have related DTCs, but that could also cause your symptoms.

One other thought: did you notice oil in any of the spark plug tubes? Leaking spark plug tube seals are very common, and changing the plugs can allow oil to drain down onto the spark plug threads in the cylinder head, which is the ground path for the spark electrical circuits. The oil can add considerable resistance, leading to misfires.

Cheers,

Don

 

I am wondering if maybe I switched some O2 sensors. Does anyone have a link to which one goes where, and would it cause issues? I made sure I marked the coil wires and put the coils in the same place as they were before. I did not check the wires, but that is a possibility, and I will do so tomorrow.

I did not notice any oil in the spark plug wells but maybe I have some now after changing everything.
My first step tomorrow would be to check the wires. Other than seeing any cuts, is there a way that I can check to make sure the wires are good other than looking for cuts?
I will then pull all the coils and check the wells.

Do the error codes point to one coil or the other?

 

You could have gotten anti - seize on the tip of a plug

On the car side of the O2 connectors , 3 wires will be the same color

The 4th wire will be different and this determines position

With a sudden change of all sensors it may be some time before the ECU learns the fine differences in the performance of the sensors readings , this has to do with no 2 sensors read exactly the same out of the store box

On your rear # 6 coil wire it will be color Light Green / Purple

# 5 is Light Green / Orange

They will all have the same common power source wire White / Pink

 

Unfortunately, no. The P0300 indicates random misfires in multiple cylinders, and P1313 indicates excessive misfires that can cause catalytic converter damage due to unburned fuel entering the exhaust. In my experience, the X300 Engine Management System is not great at identifying specific misfiring cylinders, though if you were to continue to run the engine (not recommended), it might trigger one or more cylinder-specific codes, but the codes triggered are not always accurate as to which cylinder or cylinders are actually misfiring. This may have something to do with how the knock sensors age.

 

Dhooo....Both sets of O2 sensors were backward. I will give it another test tomorrow. Thanks, Parker, as usual. I will report back tomorrow

 

You could also have a bad plug new out of the box

I saw someone tap his plugs on the ground before installing for good luck

Knock sensors connector clean ?

The knock sensors being triggered should retard ignition timing degrees which you may see on a ELM - 327 reader / device at the time of the event , an Andy Bracket may and I say may negate the ability to correct misfire at it's advanced biased degrees.

But your knock sensors do discern misfire and which cylinder / cylinders

 

Yea I ordered and Andy bracket yet it still has not arrived

 

Problem solved. Turned out to be the O2 sensors hooked up incorrectly

 

Thanks for posting your success, Phil, and thanks to Parker for posting the O2S wiring diagram.

I have added RESOLVED to your thread title!

Cheers,

Don

 

Well it is no longer resolved. I took it out for a longer drive and they came right back after 15 minutes. Not sure what the issues is. I changed out the coils thinking that might be it but did not fix it. Any other ideas. Like I said I also replace the O2 sensors. What are the chances one of those are bad

 

A new coil can defiantly be bad after warm up and others have had that

There is a test of the O2 sensors after removal using a flame that removes the oxygen and heats them to the point of reading correctly

This test would be looking at resistance on the titania sensors

This would only show a senor is alive and not calibration



I tried it myself but not successful

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

 

Hi Phil,

I removed RESOLVED from your thread title. :-(

Since you did not have the codes prior to replacing the spark plugs and oxygen sensors, it seems most likely that the problem causing the codes is related to the plugs, coils, coil wiring, or oxygen sensors.

Since the codes indicate misfires, I would tend to first focus on the plugs, coils and coil wires. It would be worth removing each coil again and checking the spring terminal inside the coil boot to be sure one of them has not fallen out or been deformed, and carefully check the coil wires again for any signs of insulation deterioration.

Problems with the oxygen sensors tend to trigger fuel trim related codes like P0171 - P0175, sensor and sensor circuit codes like P0131 - P0160, and sometimes the catalyst efficiency codes P0420 & P0430. If your scan tool can read the fuel trims via Live Data, it would be worth monitoring the Short-Term and Long-Term Fuel Trims (STFT & LTFT). Compare the two upstream sensors to each other, and the two downstream sensors to each other. Their readings should be similar and ideally less than +/- 10.

Cheers,

Don

 

I always had a confidence issue as to how well the connectors click on the coils

Vacuum check or exhaust leak as may be a too rich fuel trim misfire ( idle area only ) caused by a properly operating O2 sensor system?

 

You said you replaced the spark plugs with new ones. When you did that, did any of the plugs look different? Maybe, overly carbon-ed up? Were any of them wet? As a matter of fact, if you pull the coils, is there oil in any of the wells? You don't have to pull the plugs to see. You said you'd check, but I don't think you ever got around to it. What kind of plugs did you use?

Next you did not say whether the coils are original to the car. If they are, perhaps it's time? I don't know how many miles you have on the car, but those coils are turning 30 pretty soon.

Lastly, I would like to know if the camshaft position sensor is original to the car? It is cheap to buy and easy to replace....if you have Andy's bracket on the way, perhaps it's the perfect time?

 

Camshaft , I think you were thinking Crankshaft

With the Andy bracket ( crankshaft ) biasing the timing 5 degrees I think he would be better to resolve his issues at normal factory configuration

Yes on the crankshaft position sensor change and you can clean the face of the sensor first , this is different than connector clean

Around the car ground terminals clean , large engine ground strap on the starter mount bolt

ECU connector check for corrosion

Your crankshaft sensor ECU sockets are Black 23 and Black 26

 

I am not sure what the problem is, but because the harmonic balancer needed to be rebuilt, the power steering pump needed rebuilding, and the water pump needed to be replaced, I decided to wait to figure this one out later. When I needed to replace the plugs, I went with the NKG, and maybe that was not so smart, so I ordered some Champions to try. I did replace the coil ends with the plugs, so those should all be good. My Andy bracket came in, so I will install that, too. So, with all that, I have a lot of work to do before I figure this out.
Along with that. I am replacing the rack and pinion because I think it leaks more fluid than it is holding. Luckily, I found a Jag mechanic who will work with me at the house to help me with the rack and all the other stuff.
Once I get all this done I will report back. Thanks for all the suggestions and most of them are involved in what I am doing.

 

Could the timing gear attached to the harmonic balancer be " off "

could the timing gear be installed front face on the aft side effecting timing

Someone broke off a tooth installing the very front 34 mm bolt ( 33 or 34 ? )

Harmonic balancer change done ?

With the Andy racket installed if you adjust the Camshaft ( hockey puck ) position sensor you must use the TDC timing marks on the engine block front lower car's left quadrant , this from someone who hasn't put mine in yet

 

Have not changed it yet but last time I used a dewalt impact wrench and had no problems getting it off but this time not as much room so trying to figure out how I am going to get it off. I did buy an offset for the dewalt. Going to give it a shot. Don’t want to try the bump unless I have to and don’t want to pull the radiator to get to it.

 

One question: if I do go to the bump method, can I do it with the belts off?