LABCOATGUY
If these XJR/X300 cars are normally driven around town and not exposed to running on the open road they will build up deposits on the exhaust valves leading to loss of compression and a rough idle
There is a Jaguar service bulletin about this problem with 2 options.
(1)Replace the current exhaust valves with an upgraded "cutter" valve.- (rather expensive)
Or (2) take the car out on a highway and give it a good flogging.( much cheaper).
About a year ago I acquired an X300 from a deceased estate. It idled very roughly and two cylinders were down in compression around 110psi when the others were 160.
I gave it a hard run at the 60 mph limit for 30 miles and compression did improve on the crook cylinders to about 130.
I then dosed it with about 5 times the recommended upper cylinder lubricant and gave it a real flogging through lower gears, very high RPM and much accelerating etc. (being careful not to exceed the speed limit !!!)
for another 30 miles. That did the trick and all cylinders were now even around 160 with a smooth idle. The problem has not reappeared as it is mostly driven on highways.
Cheers

 

That is good to know but perhaps a bit worrying, seeing as this is still happening after a 1,000 journey home on American highways with an average speed of 75 MPH according to the trip computer. The previous owner had just cleaned out the injectors, so I may try something like Seafoam and give it another intense run.

 

labcoatguy
Your distance done is noted.
I suggest you do a compression check before you go any further. If the compressions are OK then it is time to start looking at fuel, spark etc.
Cheers

 

It does have an aftermarket air intake and oxygen sensors of unknown age, so I rather hope it's one of those rather than something so severe as a compression-related problem.

 

A compression check is very cheap and establishes a base line for the engine condition. I suspect you could buy a compression check gauge for under $50.
I have had crook oxy sensors in XJ40 and X300 cars.
They did not so much affect the smoothness of the idle. They either stopped the idle altogether particularly after a run on a highway or caused a dead cut when taking off from the idle (got tailgated once when taking off from traffic lights with a dead cut)

 

1997 VDP:

(1) Diff oil changed, car looked a lot like it was getting an IV drip! Nice to get that done, and not smell too much like a salvage yard afterwards. 1/2" wobble drive extension was critical to get the fill plug off with that 1997-only fancy diff-stiffener bracket getting in the way; doing the diff oil change on the 1995 XJ6 was a lot easier



(2) Took apart the arm-rest/cupholder to clean it, fixed a broken gear in the retract mechanism, and repainted the leather with some Coffee/SDC leather dye from SeatDoctor (deglaze with Deglazer from Fiebing, paint with dye three coats, then two coats of Resolene from Fiebings)

 

Fixed my power antenna so its nice now to actually have a working radio.
and also added chrome trim (well fake plastic sticky thingies) onto outer door handles.
man the look of the chrome handles is one of those little things that makes a huge difference to the look.

 

so seeing as though its a long weekend decided to get another jo out of the wqway.
i have to troubleshoot why my heater is not working.
so i started today by changing the thermostat.
as expected that did nothing.
i mean i have a nice new thermostat so not all bad. lol.
pretty sure my heater motor is gone.
i cannot hear or feel it trying to go. so either its the wiring/relay going to the moor or the bushes. will get to that job soon.

 

Replaced platinum spark plugs with the recommended Champion RC12YC copper plugs, and the idle really settled down. Also attacked an overpainted front grille surround with some paint stripper and knives to uncover the growler badge underneath.

 

The tragedy of overspray! Nice work on the growler... what were the paint guys thinking??

Also good info with respect to the plugs... might try the same thing on the Silver 1995 XJ6, which can idle a bit randomly (not enough to be mission-critical, but enough to be annoying; will be worth a whole thread post on that)

-cafe

 

G'day Guys,

Today I replaced three mini lamp bulbs, one in the N/S switch, the front ashtray/cigarette lighter and the background light for the gear shift quadrant. All tiny bulbs available at the local electronic parts shop.

These bulbs were only 27 years old so they don't last too long!

Cheers,
Jeff.

 

very satisfying to have those lights come back to life mini-wedges for the win

 

Brushed and gapped the spark plugs, all good not due to be changed just yet.
Gave the engine and exhaust a going over and found the vacuum hose from the cruise control bellows was loose, cut the end off the hose and re-installed, all good now.
Took the car for a 'spirited' drive then in for the biannual Smog Check (CA). Passed with flying colors and had better emissions that the last check (Yay!)
Looking forward to beer o'clock to celebrate.

 

Decided to tackle my spare A-frame. Its an electrolysis rust removal, extremely effective. Removed ALL traces of rust and the frame was very rusty, we're talking scaly heavy rust 5mm thick in places taken back to bare metal pretty much with almost 0 work. After two days(change the side after a day), I've simply brushed it, wiped clean, painted with some Vactan as primer and its ready for a coat of underseal now. Its amazing how effective electricity is in removing rust, I can even see traces of original primer in places

I've used graphite rods as sacrificial anodes, doesn't make a rusty soup mess like if you use some iron plates, etc and you can water your plants with the water afterwards

 

Been a busy two or three weeks:

1997 VDP Carnival Red (Ruby Twosday):

• Two applications of Liquid Glass on hood, trunk, top... interesting stuff to work with, works a treat but very finicky- have a pile of clean microfiber cloths for removal, switch to clean side(s) after one or two ft2 of wiping off the glaze

• Re-installed the clock unit after it got LED's and new LCD; might have to switch the HVAC controls to LEDs at some point to match brightness... funny how much I look at that clock when in the car
• Replaced the wooden gear shift that came with the car with an OEM leather clad one that I re-dyed the Coffee color... looks classier to me

• Almost forgot! Finally installed the Andy Bracket

1996 VDP Carnival Red (Ruby Monday, lives in Texas):

• My parents had a flat and tried to make it all the way home... they got within four blocks when the car died. The flat tire had shredded, pulled out the fender liner, and ended up melting a good bit of the RH wiring harness that runs from the a-pillar to the back of the front bumper.

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• After looking at the pictures, I realized no amount of soldering was going to fix the harness, so I contacted valdezgregorio on ebay, who has eight or nine x300's on his lot in Perris CA. He said to just replace the harness, and to make sure the PI61 connector(s) were square, not round... they went from square to round in 1997, evidently. So I ordered a salvage harness from him, had it shipped to my house, and spent about four hours labeling the connectors and comparing against the 1995 and 1997 x300s at my house. Gregorio was awesome, and advised that I remove the fender to replace the harness, which was perfect advice.

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• Had to replace the windshield washer pump as well - that got yanked out and smooshed, but the level sensor was fine, so I ordered that from gregorio as well.
• Packed up some tools, the wiring harness, windshield washer pump, and my six-year old and hopped on a plane to Texas...
• Spent Mothers Day weekend in the garage, and by Sunday afternoon had everything buttoned up enough to take my mom for a ride in the back seat, which she loved!

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• On Monday, took the car on some backroads for about an hour to make sure all the CEL's that I had taken care off did not come back on... the frayed harness fried about six fuses in the RH front fusebox, which protected all of the systems as it should

1995 Silver XJ6 (assisting my son)

• Removed, scraped, painted valve cover, replacing all of the gaskets, putting in new copper plugs from Champion (RCY somethings... thanks forum!)
• Did our first ATF fluid "replenish", including a new gasket and filter... was intimidating at first, but thankfully the 1995 has the 5mm drain plug so that got us started and we didn't look back. Used a giant adjustable crescent wrench under the car to get the 30mm nut that fastens the dipstick/fill tube to the tranny loose... PB Blaster and a gentle nudge with a floor jack on the end of the wrench and the nut came off happily. Replacing the pan is a lot easier with two people, and thankfully the exhaust pipes were not in the way too much.
• Took the car out for a test drive last night, and both drivers were amazed at how much more smoothly the car shifted!
• Used Valvoline Synth ATF Dexron VI, did one drain, then a refill and drain, then new gasket and filter, then I read some more early this morning about Dexron III vs VI blah blah blah...
• Later today I will order some Redline D4 ATF, five gallons or so, and have my son do one more flush at least on this car, getting the Redline in there to adhere more closely to the viscosity specs of the Dexon III. Almost as big a rathole online about ATFs as there is coolant! But when a longtime moderator (Don B) uses Redline D4 in his XJ's, I figure it is a wise thing to do for the cars in our stable here - one less variable to worry about.
• Finally committing to tracking down the high idle on this car after it goes into closed-loop running (normal operating temp). The exhaust manifolds have been replaced, EGR valve and IAT valves cleaning, MAS and throttle position sensors tested, O2 sensors cleaned (all four), and an intake-side leakage check with the spray bottle of water... car still tends to idle in the 1100 rpm range when up to temp, so we have a vacuum leak somewhere on the intake side. We will take it one step at a time and check each juncture and hose separately... hopefully science and logic will win out here; if not, perhaps a small sacrifice to the Great Growler In the Sky might be necessary.

Ok, thanks again to Parker, CDMA, Bob Gauff, Don B, and all of the others that make the forum so useful and... entertaining . Back to the email saltmines for me, typing with dirty fingernails that don't show up on my Zoom calls. I hope.

​​​​​​​-Cafe

 

Today I replaced the 3 power steering reservoir holder grommets (C2C-16681). The originals were cracked, broken down and causing a squeak when riding over bumps.
I also raised the reservoir a couple of millimeters so that the cooler hose so it didn't knock on the holder. Simple job but very satisfying.

 

sometimes I feel like that old smashed grommet in the lower part of your pic... and yes, the simple jobs are essential for balancing out the complex ones

 

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That is some kind of nasty mess. Glad you were able to get it all replaced, and up and running again so quickly. You are skilled.

I've done some business with @valdezgregorio on eBay, also with good results. He is a member of this forum too. Great to see the fleet is surviving and thriving with your care.

 

1997 VDP (red):

Manufactured some air vent clips out of metal from a cheap filing cabinet drawer... seemed a good thing to do on a cold and windy weekend here in NM.

(1) Re-assemble the broken plastic bits into one complete clip
(2) Spray paint the shadow of the complete clip onto the metal


(3) Cut out the profile with tin snips, drill out the big gaps w 4mm bit and the little gaps w a 1.5mm bit (approx)
(4) Dremel out the middle slots until they slide easily over the middle vanes; keep the first and last slots pretty tight... plastic version on the left, metal version (painted black after trimming and fitting) on the right:


(5) Drink an adult beverage and practice patience while trying to keep the vanes aligned AND fit the clip in place with needle nose pliers... seven vanes is a lot. If I ever have to do this again, I'll put a dab of grease or something on the pivots to keep them from moving too much while fitting the clip.


(6) Using the needle nose pliers, bend the end of the clips over to make sure that the ends stay on, which by definition keeps all the middle slots of the clip on too.




Polished the wood trim w the dremel, put a bit of grease on the unit's side clips and slid it back into the back of the center console. Another small task that makes me happy and it only took, oh, four hours start to finish. Seems so much simpler and faster in written form! Nice to know though that the clips are metal and not going to break via fatigue in my lifetime.

-Cafe

 

Took some pictures to enter it into the Greenwich Concours. Okay, it's only the Radwood Royalty section, but I did get in!