NGK Iridium IX BKR5EIX-11 --- is this the correct plug? They're gapped at 0.044" not 0.052". I've seen mention of 0.052" gap was mandated by Jaguar. What's the deal here? I've got them on hold for me at O'Reillys as well as a new battery, oil, Wix filter. Need to confirm they're the correct plugs. Thanks.

 

Everyone appears to be ignoring you, probably because the same question keeps popping up.
Yes, those are the plugs and gap is .044. There was a service bulletin many years ago to increase the gap but that is no longer needed.

 

Thanks! I searched on here and multiple threads were riddled with the gap requirement of .052" per the service bulletin. I bought the plugs anyway and they're all gapped at .044". I hope to have these installed today.

It appears as though the PO had an Interstate battery installed in the car and it was too short so they shimmed the hold-down with a 3/4" piece of pine. The battery is completely dead and from what I can tell, 5 y/o. I can't believe how huge the battery is for this car. It's bigger than the batteries in my 2000 F350 Powerstroke.

 

That is the correct Iridium IX replacement for the PFR5G-11 plug normally fitted to AJ27 engines.

Leave the gap as it comes as it's not reccomended to fiddle with gaps on Iridium plugs.
The beauty of Iridium plugs is that they produce a superior spark and at the same time take less voltage to fire it.

The 52 thou gap that so much missinformation is written about is because
Jaguar put out a TSB in early 1998 after some owners were complaining about a lumpy unsteady idle.
Jaguar decided at the time to widen the gap from .44" to .52" to smooth out the idle.
Trouble is, this has the side effect of placing more strain on the COP coils
leading to earlier failure.

My car was built in May 1998 and has an AJ26 engine and I run the BKR5EIX-13 plugs set at .44"
with no problems for the last 100,000klm.
They are just about to be replaced with same.

Always use Nickel anti-sieze on the threads...SPARINGLY!!
I use a small artists brush to paint it on the lower half of the threads and only 180 deg.
Torque them up at no more than 25-29 Nm...18-21 lbs/ft.
Follow these simple rules and you shouldn't have to touch your plugs for the next 50,000 miles at least ;o))

 

I did use high temp nickel anti seize sparingly. Mine came in a jar w/ a small paint brush affixed to the cap. No issues there.

I torqued my spark plugs down by feel. I tried the finger tight and then 120 degree turn, as mentioned in a thread here, but they were still loose. The crush washers weren't even crushed, thus not seated. My torque wrench starts at 30 lb-ft and goes to 260 lb-ft.

The spark plugs were tight. I wasn't sure the passenger rear plug was going to come out, but it did without munging up the threads.

All of the screws I removed from the covers and coils were loose. Zero effort to unscrew every single one of them. I didn't even have to grip my nut driver with a full hand to unscrew them. There was a white/yellow/orange corrosion under the coil covers. I cleaned all of that.

 

That sounds good ;o)
Get yourself a good toque wrench that reads from 5-80 lbs/ft or similar...preferably the click type and not the torque bar type.

The coil covers don't have to be tight, just a little more than finger tight 8Nm
This is why so many of these covers are cracked or broken....to many ham fisted guerillas out there ;o)=)
While you have the coils out, it pays to remove the boots and give each coil spring a little stretch to create a more positive contact between the spring and tip of the plug.
All that gunge under there means it hasn't seen much service for a looooong time ;o]

Get yourself a can of electronic spray cleaner/lubricant....easily available from any electronics shop....use this to clean all conectors, NEVER use wd40 anywhere near modern electronics!!
Always be careful handling the coil connector wiring harness, this gets brittle with heat hardened age and will add the risk of fracture due to too much handling.

You will find two relays controlling ignition....one under the cover that hides the main ecm under the false bulkhead on drivers side and the other is in the smaller of the two fuse boxes just in front of the P/S resevoir.
remove both of these and give the spades a good clean before re inserting.
That should just about cover the ignition side of things.

Bearing in mind that you car has the AJ27 engine which means you will have the two pin coils whereas the earlier AJ26 engine has four pin coils because this system had seperate ignition amplifiers attached inside the false bulkhead box along with the brake booster.
Your design dispensed with this because each coil has it's own built in amplification controlled from the ECM.
There are a lot more subtle changes between AJ26 and 27 engines than most people realise ;o]

 

Hmmm. I'll have another run at the cover bolts and back them off a bit. The covers have metal sleeves in each hole. The bolts should clamp down on the metal sleeves and not put pressure on the plastic.

I want to buy Snap-On or Wright torque wrenches, 3/8" and 1/4" drive. I only have a Snap-On 1/2" drive torque wrench now.

 

That;s OK but I think Snap On stuff is over priced...there are a number of
good quality units out there but of course the choice is yours.
The thing is get one and use it.
I also have inch/lb torque wrrench which i use on damn near everything on these motors.
It's all about learning how this design works.
It is one of the most well designed engines around and people get confused by so much missinformation and 'bar room myths'.

 

Incorrect. The AJ26 has 2 pin, AJ27 4 pin.

 

Check out your local Pawn Shop{s}. Probably under glass in showcase .
Got my Snapon 1/4"from local PS for exactly the same task as posted

 

Duuuugh!!.....Sorry, my fault....got it **** about ;o)=)

 

Not to sound to stupid. If I have a 2000 XJ8 4.0 how do I tell if it's a AJ26 or AJ27 engine? Wanting to change spark plugs. It has 140,000. Not sure when they were changed. But I'm sure it wouldn't hurt.