Hey all. This is my first post asking for help with my car. It is a 2002 x-type 3.0L Automatic. I've been throwing parts at it for about 4 years now and it's only been getting worse. For a couple years, coils would randomly go bad causing limp home mode, so I replaced them and cleared the codes and it would no longer be in limp home until one or more went bad again. When I bought the car, it had the typical error messages, dsc system fault, cruise not available, and more often than not, gearbox fault. The newest development seems to be misfires on cylinders 1,3, and 5. The codes I am getting are as follows:
P0300
P0301
P0301*
P0303
P0303*
P0305
P0305*
P1313
P1316
I can clear the codes and reset the computer with the positive cable to negative terminal for 30 seconds and the car will run much better for a few minutes but then go right back to limp home. It's gotten much worse than just the 3k rpm and 4th gear limitation. It has nearly no power. I thought since it was all three odd cylinders that started to misfire at the same time that it might be the catalytic converter or o2 sensors but I took it to an exhaust shop and they said both converters and the o2 sensors seemed to be fine. I've replaced the IMT o-rings, intake manifold o-rings, and throttle body o-ring. I removed the brake booster pipe and blew in to one end and air flowed freely. I blew in the other end and it was solid, so I assume it is working properly even though visualy, it is quite deteriorated. I put some super glue around the seam to make a permanent seal and checked it again by blowing in to both ends and the check valve seemed to work properly. I removed the intake manifold and found something very interesting. There is a very small amount of yellowish residue around the openings for cylinders 2,4, and 6, while theres a rather large amount of sticky black buildup around the openings for 1,3, and 5. I have also replaced the fuel pump and filter and had the injectors cleaned out of vehicle as well as in. My jaguar mechanic has run out of ideas on what could be wrong. I took it to the dealer and they said "It might be the timing" and they want 1600 dollars just to look at it, regardless of if thats the problem or not. And then who knows how much more money if that is the problem. I took the valve cover off and nothing looks obviously wrong to me, although I am not a technician or anything. If anyone has any ideas or suggestions I'm all ears. I love this car and don't wanna see it go. Sorry for the painfully long post, but I'm just trying to provide as much information as I can. Please let me know if I left anything out or if I can clairfy anything. Thanks ahead of time for any help you may have to offer. Thanks for your patience in reading this as well,
Nate

 

just wanting to make sure when you said you have replaced the coils you were replacing the coil and the sparkplugs and also on the intake did you replace upper and lower gaskets. i've never seen any xtype jump time. not saying it isnt possible just doesnt seem like the most likely scenerio. also while you have it at the dealership could you find out what your long and short term fuel trims are at for both banks. wondering if its a lean condition causing the codes. due to your rev condition i would also check into your maf sensor. hope you get it fixed.

 

Thanks for your reply lightninfil. I had the maf cleaned, no change. My mechanic put a new one in, no change. Every time I have any coil replaced, I've also changed the spark plugs just because I'm in there anyways, and they are cheap enough. I didn't replace the lower gaskets, I guess that's next on my list since its relatively inexpensive. The dealership didn't want to give me any of the diagnostic info they found but I do have a cheapo obd2 reader. I have some screenshots of the info I found. I'm not sure exactly what I'm looking at to be honest, but I will post them here. The scanner says it's running in closed loop.
At idle, the reading changes between two things. The first says:
02 Sensor 2, Bank 1: 0.815 V @ -1.6% st fuel trim
02 Sensor 2, Bank 2: 0.830 V @ +1.6% st fuel trim

The second:
02 Sensor 1, Bank 1 (WR): 127.996 mA, Eq. ratio: 0.999
02 Sensor 1, Bank 2 (WR): 127.996 mA, Eq. ratio: 0.999


At 3k rpm it flashes between two readings. The first is as follows:
02 Sensor 2, Bank 1: 0.770 V @ -0.8% st fuel trim
02 Sensor 2, Bank 2: 0.705 V @ +1.6% st fuel trim

The second reading it gives me at 3k rpm, I don't understand at all but here it is:
02 Sensor 1, Bank 1 (WR): -0.441 mA, Eq. ratio: 0.985
02 Sensor 1, Bank 2 (WR): 127.996 mA, Eq. ratio: 0.999

I don't see anything in terms of long term fuel trim, just short term. I'm not sure if this is because of the constant code clearing and cpu resetting or if I don't know where to look, or if my reader simpy doesn't give me that info. I really hope this helps someone maybe think of something else the problem might be. Chances are I've left more out, but please feel free to scrutinze more :P and ask more questions and give more advice. I really appreciate it very much.

 

are those the only codes you have? also your short term fuel trims seem fine.

 

Those are all the codes I am getting. I took the valve cover off in the meantime and everything appears to be normal. Nothing looks broken or out of the ordinary. every part I can see seems to be intact with no visible signs of damage. The timing chain seems to be in good condition. i took the fuel rail off and i can see the intake valves. The two pairs of valves on the left side (from sitting in the car) seem to have rather large buildup of gunk on them that is somewhat gooey. It seems like the valves are unable to close and cause a proper seal. Could this be a symptom of the problem, or the problem itself? I really hope more people read my thread and chime in. I'm going to do a compression test tomorrow and see what I find out.

Also, is there need to be concerned about the last set of readings i posted previously?


The second reading it gives me at 3k rpm, I don't understand at all but here it is:
02 Sensor 1, Bank 1 (WR): -0.441 mA, Eq. ratio: 0.985
02 Sensor 1, Bank 2 (WR): 127.996 mA, Eq. ratio: 0.999

I have no idea of what any of that really means but I do notice a massive difference between Bank 1 and Bank 2. Any information or ideas or theories that anyone may have about anything in this thread are more than welcome.

 

I'm getting a bit desperate here. Can anyone give me any more advice or suggestions? I know theres many people on this forum that are incredibly smart and experienced with this kind of stuff and I'd really love to be able to learn more about diagnosing a newer care like this, as well as saving my baby in the process. Should I make a new thread with a shorter post so I get some kind of response, if any?

 

nateman, Like any forum you just have to give people time to respond. It's better to have to wait for a good answer then get the wrong one quickly! I'm waiting for someone to answer you too so I can learn something also. Good luck solving your problem.

 

Did you replace each valve with a new gasket??? You cannot use the same ones once the intake manifold is removed, it will continue to throw these codes until you replace the gaskets. Had this happen to me when porting the intake manifold on my 2002....

 

I have replaced every gasket and o-ring that I can find on the thing. I really wish it was something so simple. All three cylinders on that side of the engine are misfiring. Last time I had the manifold off, I replace the upper and lower gaskets, and the IMT o-rings. I replaced the throttle body gasket too. No help. I'm still extremely grateful for your reply, especially on thanksgiving :P I'm begining to think that the timing is off since it is all three cylinders misfiring, and they all started misfiring at the same time. Would bad timing combined with heat from the catalytic converter cause build up on the intake valves leading to them no seating properly? The converter is practically up against that side of the engine.

 

Perhaps this sounds a bit trite to mention.... nor do I doubt your aptitude for automobile repair, but.... Have you tried a complete 'reset' after re-seating everything? Fully disconnect the battery (both poles) and unplug and re-connect the ECU. This has actually worked before. or.... have you re-checked your sparkplugs? are they seated correctly? are they the correct gapping? just some quick-fix notions.
Forgot to mention cleaning your MAF sensor. Have you tried that? A filthy MAF sensor can throw all kinds of codes

 

Thank you so much for going out of your wat to respond j_bond. No need to worry about doubting my skill or putting me down or anything. I'm here to ask for help because I am not a professional mechanic with unlimited knowledge. I wish I was! I've pretty much tried everything that doesn't cost money, or costs very little. One of the first things I did was clean the MAF, then had my mechanic replace it. That still didn't fix it or change anything. Ive tried three different kinds of plugs, and double checked the gaps. I've done any and every kind of "reset" on the computer I can find on this forum. I have also cleared the codes with my scanner but the same codes keep appearing. I'm really beginning to think its something wrong with the intake valves and/or the timing chain and tensioners on that bank of the engine. If anyone has any advice on how I should dive in to checking timing on this thing please let me know. Or if one of the guys here that specializes in engine stuff could give me some pointers on my situation on general, that would be greatly appreciated. I have a very strong feeling this is not something as simple as a dirty sensor or a vacuum leak. I hear no leaks, and I see no hoses or tubes that appear damaged. The engine idles nicely with no load, its only once the rpm's get higher in park, or once its in drive with a strain on it that it runs rough and throws codes and enters limp home mode. Tonight I'm going to take the timing chain cover off and see if all the markings on the chains are properly aligned and if all the tensioners and guides look good. Does anyone think it might be a bad catalytic converter? Maybe it is clogged up and is not allowing the exhaust to fully leave the cylinders until the intake valves open. Wouldn't that explain the presence of all the black oily gassy buildup on the valves and in the intake manifold? As I keep saying, any and all suggestions and theories are welcome and appreciated.

 

Clogged cat is a strong possibility. unbolt the exhaust and check, I have seen cats break up into pieces inside the piping and block the exhaust. Sorry for the delay in my response

 

Thanks j_bond. I will do that first thing when I go down to the garage to work on it this morning. I took both valve covers off to check the timing chains, not that I really know what to look for besides obviously broken pieces. I found the timing chain on the three cylinders closest to the front of the car to be somewhat sloppy at certain points throughout its rotation. I can wiggle it back and forth on the sprockets on the camshafts at certain points. When I push down on the section of chain between the two sprockets, the intake cam rotates enough to notice which leads me to believe there is slack down below the intake camshaft. I have little experience in timing stuff, but this seems to be the problem with the car to me. I may be making a noob mistake here, but aren't the cylinders towards the front of the car 2 4 and 6? Even though the computer is saying the misfire is on 1 3 and 5? Im quite confused by this whole predicament. Thanks for all your replies J_bond, lightninfil, and razkid. I think I'm actually getting much closer to fixing my Jag. I'm just confused as to why it seems the chain on the front seems to be sloppy, while the cylinders on the back seem to be showing symptoms. The back timing chain is consistently tight throughout several rotations of the crank shaft. But it's those valves that were covered in buildup and all the openings in the intake manifold, as well as the gaskets, were covered in black goo. The back sparkplugs were also covered in a black build up. Not burnt though. Seemed more of a result of running rich. I'm thinking after i pull the engine and take the timing chain cover off, I can see if it looks like any of the guides or tensioners may be bad too. I'll keep posting anything I find.

 

Hey guys have you ever figured the culprit of this problem with the odd cylinders? I'm having the same issue. My car runs perfect when cold but as soon as it warms up it struggles to rev up and throws P0300, P0301, P0303, P0305 and P1313 with Restricted performance. Please share if you found a solution, thanks.

 

After reading this over, I continue to wonder if there isnt' something that goes wrong with the wiring itself that goes to the coils/plugs of the odd cylinders. The consensus seems to show that this constantly happens when the car warms up, so it really seems that the expansion somewhere due to heat is creating some kind of malfunction. Seems to boil down to some kind of electrical problem, could even be something going bad in the corresponding section of the wiring harness to the fuel injection system, coils, etc. Many people report similar issues when water gets in and partially ruins the ECM. It works for a while but goes haywire when it warms up.

Anyone try changing the ECM, various wiring harnesses, etc.?

Thermo has a great post from another similar thread (looks like we come to the same conclusion):

 

I had all same codes. Just earlier today. Changed Intake Gaskets. they looked good but once you take them out you can tell they were bad. Also a coil spring was not on right. I had this problem for like a year. Fixed stuff from MAF to IMT rings. smh

 

Plus my cat is bad. Trust me. CHANGE THE INTAKE GASKETS. and any bad coils

 

I know this an old thread but did anyone ever solve this problem. I have this same problem and just about to try and find the problem. Is that yellow /green wire common to 2, 4, and 6 as well.