Hello All,

Just my second post only after I really got my first one all wrong. My second jag this one a 03 Xj8 sport with 117k on the odo. I bought the beauty as a bank owned repo. All records and maintenance. Production year may of 2002. Car has no bypasses or rigged items.

Just got the car to my shop today, I checked oil clear and Radiator fluid as well. All good no burn marks on the oil dipstick either. Placed new battery in unit and pulled codes had, P0300,p1316.

Pulled the plugs they were NGK iridium incorrect gap, and fouled. Replaced with new Bosch.
Drained fuel refilled with 98 oct.

Started vehicle runs very rough and then stalls now codes are P0302,P0304,P0305 and P0308.

Wanted to know your thoughts before I pull valve cover gaskets to check chains.

PYatsko
2003 Jaguar Xj 8 Sport
1998 XJR
1976 930

 

May want to check this post:
https://www.jaguarforums.com/forum/x...t-fixed-63761/

 

I have been using Bosch in my XK8 & S-Type and they work just fine. Now that the plugs are replaced and the oil and coolant are ok you should check the air filter as well. I would add a can of BG44K fuel additive and run the car. Your wanting to check the tensioners is not a bad idea.

 

Gus, I appreciate your quick response. I will be changing fuel filters before I pull the valve covers. Is there any way to determine If I am missing something. I have also checked all relays and fuses. It almost appears to have a spark or compression issue. On one attempt today the cars P0codes were all even then they were mixed. Does this make any sense? I am learning why I love the flat six turbo.

Pyatsko
2003 Xj8 sport
1998 XjR
1976 930

 

Your problem could be a number of things from coils, fuel injectors, throttle body and a host of other things including the tentioners. You replaced the plugs and you are going to check the tentioners, do that and see what you find.

 

Since the codes appeared with the plug change, that process may be the fault. I would switch plug brands and retrace your steps in the plug change to be sure it was done right.

 

Update
removed valve covers tensioners are good no slack. got ngk plugs going to clean throttle body today. electronics on throttle body seem to indicate a slight stick in plate movement. what should my pressure be in the fuel rail with key on engine off versus key on engine running? thank you for the great help

 

check those coils! youd be surprised on how 1 bad one can really throw things off. especially since your plugs were fowled and clogged.

also try posting this in the other XJ section, this section says 03 but thats European 03 its really for 2004 n up.

lol by the way also see your from gainesville, do you need a great shop reccomendation who if anything else will give you good advice and does a great job?

 

Coils! Had similar issue. Replaced #8 coil. All is fine. Bosch plugs have a recent issue. Try another brand.

 

We should really move this to the X308 forum!!!!!!!!!!!!!!!!!!!!!!!

bob gauff

 

When you check the tensioners (hope it's not too late) make sure you can see the body of the tensioner. If it is dark red plastic, you should replace. The body will crack and split, and it will not be immediately obvious. I have read reports that the iridium plugs are the only way to go. I can't speak from personal experience, as I have always used the NGK iridium and they have been great. Also, oil in the spark plug wells can wreak havoc on the ignition system and the coils. Just thought I'd throw those nuggets in.

 

How do I go to that forum? Guys very very much appreciated how you have treated my questions so far. If i can do anything for you on Porsche 944,911,930 let me know. Once I get an opportunity after the "dinner" I will get to replacing the new ngk iridiums. One last thing Would coils cause the no idle condition, meaning will they actually cause the throttle irregularity.

Thanks As soon as I learn how to move the post I wil.

 

After you do your checks and cleaning let us know how you make out. The moderators will move your post for you.

 

Thanks Everyone have a terriffic turkey day!!!

 

The car has a build date of mid 2002 actually june. I didnt think the tensioners were still an issue as far as the cracking problem. I did check for slack and function all appeared fine.

 

You're correct, the build date puts you 10 months past the plastic tensioners, so no worries there.

Fuel pressure at the rail should be 40psi+/- on cranking.

Connectors need inspecting and cleaning, every one you can see and get at around the engine harness. Particular attention to the throttle body connectors.

Cleaning up the throttle body and MAF sensor is another thing to do as a matter of course when under the bonnet of a new to you Jag.
The MAFs is held into the induction tube with 2 pozi screws, pop it out and blast it with CRC electrical contact cleaner, you'll be able to make out 3 sensors. Set it aside to dry out and work on cleaning up the throttle body, remove as much gunk as you can. A proper job is to unbolt it and clean the backside of the butterfly also.

I'll say you have one of the last 308's and as such a potentially great car, once you've these little glitches sorted it should be great, good luck!

 

Turkey update repair, Both valve covers removed chains etc are in great shape not damage to the eye. Repalced valve cover gaskets. Cleaned MAF, Replaced plugs with NGK iridium. Still using the coils that were on the car. Ran the car and this time still no idle but also no individual P codes just the 1316 and 300.

Car also has discerable knock like when used with the older ngks or the bosch plats.
However the intake housing has a low thunk noise now sounds like dentonation problem or fuel.

Going to replace fuel filters tomorrow car has 3/4 tank of 98 octane fresh as of 1 week ago.

Throttle response is much better now that body was cleaned and stripped of gunk

however car will not maintain a regualr idle at the exhaust side a puff puff irregular exhaust noise is noticeable.

Any help any thoughts

tHANKS

 

Use this link http://jagrepair.com/images/AutoRepa...J27%201999.pdf and look up your P300 & P1316 they all seem to go back to misfire and if you replaced the plugs and cleaned the TB you may have a problem with fuel. It could be from fuel pressure to fuel presentation (clogged injectors) or a few other things. Take one thing at a time, replace the filter and check the fuel pressure for now and see what you have. You did say you do not have any other codes?

 

gus thanks
no other codes, would i be getting other codes if in fact a coil was the cause? if it was in fact a low resistance coil wouldnt i get a specific cylinder coil code? am i correct that these coils cannot be accurately tested?

thanks

 

I have no idea how to test a coil with the exception of one that set a code. In that case you swap it with another cylinder and see if the code changes to the new cylinder location. I would say if you do not have a cylinder code you do not have a coil or spark problem.