Just when I thought I was getting to know my car, I learn something new. My car was manufactured in 3/97. According to an old thread about spark plugs, my engine is an AJ 26, not 27 and I should use NGK BKR6 vs. what is shown on parts websites as BKR5 series plugs, at least when referring to iridium plugs.


So do the parts sites have it wrong?


Thanks!

 

The sites may have it wrong, but it is a very small difference. The 5 is in a lower heat range than the 6. What are the plugs in your car now? If they have served you well stay with them. If not take your pick between the two you posted, either will work, and run them for awhile (800-1000 miles) and see how they look after that. Here is a link to a PDF for NGK plugs. http://www.ngksparkplugs.com/docs/te...bols_plugs.pdf

 

Thanks Gatekeeper. I would presume that the original plugs are in the car because it has only 57K. In other words, they are whatever was installed by the factory. I have not pulled them yet. They are not "due" to be changed before 100K, but I thought I might change them at the upcoming 60K, just because of their age.

 

I have used Bosch for years in both my Jags with no ill affects. The plug I have been using is Bosch Platinum 4 or Double. Unless you have an XKR your XK8 will run just fine.

 

Thanks Gus. Is this the part? I note that the gap is preset. Is it preset to.052?


BOSCH Part # 4418 PLATINUM+4

 

I never had a reason to test them when you see a "4" you will know what i mean.

 

Thanks Gus. I have a feeling that I asked a dumb question with regard to the "4". Are they good for 100k like the originals?

 

I ran them for around 65/70 k. Not hard to change so I changed them no real reason.

 

Thanks again Gus. Having now seen a picture of the 4's, I can why no gapping. I'll give them a try. Right now I'm having a devil of a time sourcing the AJ26 cam/spark plug seals. No use starting the spark plug project until I have those.

 

As you have an early one like mine (11/96) you will likely need the ones like this
I need to change mine as my car has 98k miles and I have no idea if they have ever been changed as yet.


Dave

 

Thanks Dave. I also found them at FCP Euro.


https://www.fcpeuro.com/products/jag...-xjr-nca2578bb

 

I'm not keen on the Bosch and see no reason to move away from NGK.

Within the NGK offererings, you can move around on heatrange and materials type.

I use the Platinum since I am not expecting plugs to last 100K.