My car runs very bad and shakes until it is fully warmed up. The check engine light flashes sometimes too. The codes are misfire cyl 2~6 and p1316. Any ideas?

 

I would first start with replacing the fuel filter if you haven't in the last 10,000 miles. Next, get your hands on a can of throttlebody cleaner and then remove the intake tube and spray the throttlebody really good (if you see brown, squirt it, ensure you push the butterfly valve open and you spray the edges of the valve too).

Lets see what you have at that point and then we will dive deeper into the issue.

 

It also could be you coils. How many miles you have on it? I may be wrong but thermo, Is 2,4,6 in the back under the intake?

 

my does the same thing i just put in new plugs today and changed the upper intake gaskets but it still does it i am thinking i need to change the lower ones too

 

I changed the filter and cleaned the tb. Didnt help. The plugs are fairly new two. Also I dont see how all the coils could go all at once. i'm starting to think the timing chain stretched out..its funny though cause after its warm it drives a lot better

 

don't forget the MAF sensor. also what are your fuel trims?

 

Maf should be good otherwise the code would come up. my fuel pressure is at 55. I am going to clean the egr tonight and see if that helps

 

Dr. Dome, I would want to double check my diagrams, but I believe you are correct.

MyJag, not to ask a silly question, but did you regap the plugs when you went to install them or did you say "they are gapped already, so, no need to regap"? The gap that the manufacturers have is wrong as Jaguar put out a newer gap measurement (slightly smaller than the old gap as I recall). So, it is possible that this is what you are experiencing. Then as the motor gets warm, the heat in the intake air is enough to allow for a good spark.

 

So far nothing worked...is there anything inbetween the coils and computer that tells the coils when to spark? .. This is a tough one

 

Myjag, let me correct something that is wrong above. Cylinders 2 and 6 are under the airbox on the side of the motor that faces the front bumper. So, you are good in that respect as getting to the parts is going to be much easier.

As for something between the coils and the computer, there is nothing. But, do not fret at this moment in time. What I want you to do is to remove the airbox so you can get at cylinders 2, 4, and 6. Remove the coil for #2 (left side if you are facing the engine bay) and look at the inside of the coil at the rubber boot that is there. See if you can spot any white powder there. If so, you have a coil that got hot/the rubber is degrading and now the spark can jump through the boot to the block, resulting in a weak spark and your misfire condition. Next, look down the plug well and see if you spot any oil (may be on the end of the coil boot too). If you see oil, it is possible that this is the source of your problem and odds are, you are going to end up replacing the valve cover gaskets for this side of the engine. Finally, remove the plug from the #2 cylinder and look at the end of the plug. It should have a nice dark gray color to it. If it is wet, then you have either a bad injector or an oil issue. Also check the gap to ensure that it is correct and not excessive. Also at this point, do a check of the wiring going to the #2 COP. Replace anything that does not seem correct.

When reassembling, put the #2 plug back into the #2 cylinder and tighten accordingly. Now, remove the COP from #4 cylinder (the middle COP) and install it in the #2 position. Install the old #2 COP in the #4 position. Reconnect all the connectors.

Repeat the second paragraph on the #6 cylinder with the exception of switch the COPs around. Start up the engine and see what you have. Drive the car with a little bit of spirit, especially when it is not up to temp to see if you can cause the codes to come back in. If the codes change to #4 and #6 misfiring, then you have 2 bad COPs and you need to replace them.

One last thing you may want to take a look at is if you follow the wires from the COPs, you will notice that on the front left corner of the engine (by the ABS block), you will see where all 6 of the COP ground wires meet in a ring lug that is bolted to the motor. Remove the bolt holding the lug in place and clean all the surfaces really well. Then reinstall the bolt, tightening it down snug again. This was assembled with glue from the factory and over time, this can cause a high resistance, leading to some of the coils not getting full power.

 

I have misfire 2~6 meaning 2,3,4,5,6...i will try that ground as soon as I get home...do you think it could be my timing chain? Any way to check that without pulling the motor?

 

MyJag, if you are getting misfires on all those cylinders, then that pretty much only leaves but 3 possible things (ECU, ground connection, and power wire issue). If you have an issue with the timing chain, that would not go away as the motor gets up to temp. As for checking it, you would have to do a lot of disassembly to be able to see the timing marks to check that. Besides, the ECU adjusts the valve timing based on how the motor is running and if the chain was stretched, it would not be able to over come it. The same is true if you managed to somehow jump a tooth. So, I would find it very unlikely that it is the timing chain (as it is a true all metal chain). If the tensioner failed, this would only cause one side of the engine to have issues and then it would cause the motor to lope (erratic idle), not so much a rough running condition.

Check the ground connection and lets go from there.

 

I have misfire 2~6 meaning 2,3,4,5,6...i will try that ground as soon as I get home...do you think it could be my timing chain? Any way to check that without pulling the motor?

 

Pulled the bolt cleaned everything still misfiring...can it be the coolant temp sensor?

 

Myjag, if it was the coolant temp sensor, then you should be getting other codes associated with that problem. Send me your e-mail addy in a PM and I will send you the TSB relating to this problem. Maybe that will help spark something for you.