safulop

OK you gurus can help me settle a discussion on a Jaguar forum.

I've been looking to buy a Jaguar XK-R, which is supercharged. Turns out a lot of owners getting up to 100K miles are finding that their catalytic converters are completely clogged and have to be replaced. Apparently this is a problem with blown engines?

Anyway somebody there told me that our high-mile 928 cats are probably all clogged too, but we just can't tell because the engine is naturally aspirated. But nevertheless we are getting a power reduction, it is just not so obvious of a problem. Is this true? Are high-mile 928 cats generally clogged?

hernanca

I have 243K miles on the original cats of my 86.5 5-speed. I don't believe they are clogged, but at the top of my list of the many to-do's of this car is to check the health of the cats. I will post here when I know one way or the other.

I've always heard that rich fuel mixtures will ruin cats. Since the XK-R's come stock with a supercharger, I would believe the tuning was correct from the factory. I would also want to believe that they use high quality cats, as we do. Maybe the XK-R's with the clogged cats have either through age or user mods caused their tuning to go to the rich side? The tell-tale sign of a rich mixture is a layer of black (soot?) inside the exhaust system.

I know supercharged motors pack more exhaust per cylinder cubic inch than a NA motor, but I would think that if each setup had an appropriately sized exhaust system, the less powerful motor, whether supercharged or NA, would notice the difference of clogged cats more - and the bigger the motor difference, the more noticeable the clogged cat difference? Think A/C systems, hills, and old VWs.

safulop

I am kind of newbie to Jaguar, but the consensus seems to be that basically every XK-R has to have cats replaced by 100K miles if not before. There was even some kind of tech article that was referred to on the subject. They get completely restricted in flow, so bad that the cars won't even run.

Ninespub

Watch out for the dreaded supercharged Jaguar equivalent of our 928 water pump/timing belt issues: A small $15 US-$40 Can hose that deteriorates badly after about 50K, requires removal of the entire supercharger system; and if you don't and it breaks, it will overheat and you just lost your engine. Ask me how I know. BTW, I almost went XKR too - they are a beautiful automobile. I have a supercharged S-type R sedan as a DD.

safulop

^^^^^^^^^^^
Thanks for the tip. These Jaguars, as beautiful as they are, seem like sweet disasters. On the forum I am reading about problems afflicting 30K-milers that we only see past 100K miles. I've read about drooping headliners, separating leather dashboards, dead MAFs, and yes, the catastrophic overheating engine you describe. And all this on 30K mile cars! I don't know, it seems like a sour well.

Ninespub

Jaguars are like a beautiful woman: They are delicate, typically high maintainance, the little things they do (or don't) do not make sense and they cost a lot of money to keep; but when you're inside them life is good. Having said that, There are millions of guys out there that have been with beautiful women who walk away, muttering "I don't care how good she looks, That beeotch is driving me nuts!"

BTW, you didn't mention the convertible top "green showers"when the hydraulic system explodes all over you or A-arms that last 50K miles and 100K mile "lifetime" transmissions with no fluid change or serviceability. The early XKR's can be bought for stupid money and the supercharged engine is a blast, but I'd stick with '05/'06 if I were looking. Like the 928, provenance with service records and a PPI is a must, and you will have an enjoyable ride. You just have to build in the repair-replacement of known issues.

I've had my S4 for over 16 years and in the past 3 yrs put over $20K into a mild-mod/restoration. Might get to drive it for the first time in those years in a few weeks and then put it away for the winter, only to drop another $3-5K in the spring to "finalize" the job........Hah! The 928 is far superior in build quality to the Jag but I still might get an XKR convertible for my wife's Summer car.

safulop

Well you know that as an S4 owner I am not averse to spending the big bucks to maintain a vehicle, but your comments are pushing me toward my plan 'C' to replace this old Porsche. Plan A was going to be a 996, until I found out about the intermediate shaft bearing Achilles heel. Plan B was the Jaguar. Plan C is a BMW 650i. Please tell me these are half-decent quality and won't fall apart after 30K miles?

The Forgotten On

No, they start to fall apart as soon as the warranty expires

Dan87951

The v8 supercharged engine from Jaguar is a monster. I have driven a few and they feel a lot more potent than the 375HP that they claim to be. If you're interested in one of these cars, it's mandatory that the chain tensioners be upgraded to the latest metal versions (primary and secondary). If the original plastic chain tensioners break, you're out an engine. The XKR and XJR are great cars and an absolute bargain on the used market considering how much performance you get for your dollar.

Ninespub is a good Jag resource and is passionate about the brand. One of these days I will find the right XJR -- I did look at a black one on Saturday that was advertised as in "good condition" but was a total rat bag.

safulop

I've moved on to Maserati now; they seem to have better build quality than Jaguar. At least, it's hard to find people complaining online about how they fall apart at 30K miles.

hacker-pschorr

I have zero experience with the supercharged version, I've been maintaining my mothers XK8 since she purchased it with 60k miles on the odo.

Her car is approaching 190k miles (that's not a typo) has only left her stranded once due to a faulty transmission switch. We've done nothing but routine maintenance to this car. Timing chains are original.

safulop

The only way I can make sense out of the conflicting Jaguar crosstalk, is that there is a certain proportion of the cars that are lemons, and the stories about them have traveled and spoiled the batch.

safulop

The supercharged XK-R claims to be 420 hp I thought, not 375.

hacker-pschorr

That's true with almost any car. You can throw a stick and hit multiple sites proclaiming the Ferrari 355GTS is the worst car ever made. Yet my father and multiple friends own or have owned one only to find them extremely reliable, and from personal experience working on a 355, not bad on the maintenance end when needed.

There is a now infamous article stating as fact the 928 engine block will crack.

Spend a day in the 996 forum you will come away thinking it's the worst car ever designed, a ticking time bomb that cannot make it to the end of the driveway without tearing the engine apart.

There is usually a smidgen of truth in these storied (except the 928 engine cracking...no idea on that one) and in the case of the Jaguar:
1. It's British so everyone "knows" the electronics are crap. People ignore the fact that this was the first gen of Ford electronics (a good thing)
2. They are just "rebadged Fords" - the X and S Type share Ford platforms, the XK does not....total hogwash
3. Engine block coating - this is a legit issue and from everything I've read boils down to fuel quality where the car lived. My mothers Jag was delivered new to Northeast Wisconsin where we are void of sulfuric reformulated gasoline.

Now that's not to say they don't have their quirks. Here is how I fixed the tail lights:
http://www.jaguarforums.com/forum/xk...esolved-35083/

The coolant system has one "octopus" hose that is a royal PIA to install and get all the air out (this is a difficult car to burp...).

Yes you must be diligent with the top hydraulics, like any other fluid you have to change it.....

The battery is huge & very expensive, don't even think about buying a cheaper generic one if you have a convertible

The cam-chains are just like a timing belt, my father has been too stubborn (he also went 7+ years on the timing belt on his Ferrari). After 190k miles I somewhat agree why do them now, but normally this is something to figure in. IIRC 100k+ miles is typical and miles only. Unlike a belt you don't do chains based on age (usually..)

Leaks - like any car there are known places these will start to drip oil. IIRC the supercharged ones have an oil cooler with lines that are prone to this and they can be expensive. Don't quote me on that though....

Bottom line, research, research, research (the forum is great for those cars) and get a thorough PPI.

I chalk the performance of my mothers car to being driven, a lot. No car likes to sit and her's never did (except for winter).

That's what I can remember, YMMV, do not pass go, do not collect $200.....

Lastly, why hasn't I moved this thread yet???

safulop

Yeah I spoke with a Maserati owner who also has an XK-R--he's had it for 80,000 miles since buying it used, and nary a problem with just routine maintenance. I mentioned to him stories of suspect build quality, and he proclaimed that to be "a vicious canard." And yes, I too got pretty scared by the IMS bearing issue in the 996 forum. But you know, I remember lurking here before buying my first 928, and while a lot of problems do get discussed, quite naturally, I don't remember thinking that there was talk of 928s being nasty or having general problems. Well now, there was that TBF thing...