While I'm replacing the ABS/DSC module I figure I'll do a few other things.

I have that oil leak on the back of the intake manifold so I guess its time to fix those. I have 148,000 miles and to my knowledge the plugs and coils have never been replaced. Guess I have been lucky from what I have read on the forum.

1. Does anyone have suggestions for replacement spark plugs? I have used Bosc Platinum +4 on other cars and had good luck. Does anyone have any experience using these or a recommendation for the best plugs for this application. Looking more for gas milage than performance with a 3.0L.

2. Does anyone have any recommendations for sourcing coils or makes/suppliers to avoid?

Any help would be appreciated.

Thanks in advance - Smokey73

 

Some items may be in the FAQs thread about Ford/Lincoln LS/etc parts. I think the coils are.

The oil thing is likely the IMT O rings (see FAQs for fix).

Try FAQs for plugs, too. They may be iridium rather than platinum (the STR's are).

 

Jagv8,
Thanks for the info but I couldn't find the thread you were referring to on FAQ. Is this on this jag forum s-type or some other forum? If you have the link I'd appreciate it or some other tip on getting to the info.

Thanks in advance.

Smokey73

 

Hi Smokey. I lived for two years in Wilmington and Hampstead (Topsail), NC. First stop was Beufort. Jag used NGK in its cars. Use the "Search Forum" feature for threads on coils and plugs.

 

There are no miracles to be found in spark plugs. From the very cheapest to the ultra expensive multi-tipped unobtanium coated Wunderplugs, they all simply ignite a few molecules of atomized gasoline that happen to be in proximity to the electrical arc. And that's it. The remainder of the conflagration occurs as the flame front spreads away from the initial ignition point meaning that the 'hotness' of the spark becomes irrelevant.

A plug either sparks and lights the fuel or it doesn't, much like your backyard grill. Whether your steak is rare or well done doesn't depend on what was used to light the grill.

The only advantage of platinum, iridium or other exotic material plugs is durability, meaning 100K miles vs. possibly 10-15K miles with conventional plugs. There are no gains to be had in mileage, power, etc. no matter what the advertising copy might claim.

 

Hotness of the plug is VERY relevant, especially in boosted or high compression engines. But everything else I agree with. As long as you’re getting good spark, you'll get a full burn.

 

If you're referring to heat range (keeping the electrodes clean) it's important in all engines. If it's the hotness of the spark, that has nothing to do with the plug but by the characteristics of the secondary ignition system ie. 'the coil' and associated hardware. Standard ignition systems fitted to cars since WWII are more than sufficient to fire anything short of a top fuel dragster.

 

Ah, yes Sir. I miss read what you meant by "hotness" of the plug. I was in fact referring to the heat ranges. I know it is important in all engine, I was emphasizing that in boost / high compression engine it is easier to make things go boom if the wrong heat range is used. I’ve been there, and I didn’t like it. Lol Detonation, or pinging can happen in any engine with the wrong plugs I agree.

 

There's little reason to deviate from the OEM specified heat range- they've done all the engineering and testing to determine what works best. Second guessing and making a mistake with too hot a plug can induce pre-ignition in short order. That can get nasty as you mentioned.

Detonation is very different from pre-ignition BTW.

 

If it were my vehicle and I planned on keeping it along time, here is a link that may help you out!

Definetly go with the iridium plugs!


https://www.jaguarforums.com/forum/s...tenance-49309/

If you don't bother reading through all the posts, remember this the coils in the 2003 MY and up are the 4 wire type NOT the 2 wire!

 

Yea, I know most people think detonation IS pre-ignition even though they are in fact two very different phenomena like you said. I was just trying to speak easy.

Anyways, we are agreeing in the most argumentative way, so Cheers.

To the OP, in summary. Just open your book, look at what's recommended and go buy them. No reason to deviate unless you are heavily modded...

 

Start in the FAQs and just look for
parts

(found a few relevant things including the ones I meant, almost instantly - I can recommend just opening the FAQs page and then using your browser's Search-within-page which in Firefox is Ctrl+F)

Also looked for
IMT

similarly found it instantly - I really do find firefox's Find (Ctrl+F) works once you've the right page open