hi, has anyone tackeled removing the fuel rail in order to get at the fuel injector, the car sat for 10 years on the same tank of fuel, i had done complete tune up, refilled the tank with fresh fuel and added two bottles of fuel injector cleaners, any suggestions would be much apreciated, thank you!

 

You might want to check your long and short term fuel trims before ripping things apart. Bad injector would let more un-burnt air into system and the trim would be enriching for the unexpected air. Spark miss would let excess hydrocarbons in and would likely lean out the mixture.

 

Hi oldKarz, thank you very much for the reply, what I have learned on youtube regarding the fuel trim is the 14:1 ratio, and sorry it took me a while to respond and the reason being is I dont know where to start, I was assuming the injector is clogged because the bad gas, However I would love to trouble shoot it step by step and even if it takes some time because Im retired and I do have other vehicles to drive, hope to hear from you, thank you!

 

AFAIK, your '04 XJR and my '05 Xj8-L differ moslty in your having the supercharger, stiffer damping, a few bits of nicer interior trim, etc.

Mechanically, they are otherwise much the same.

and ....

Both 4.2 V8's use a Throttle-Body Injector, @ primary electrically-driven in-tank pump output pressure - around 55 PSIG...

There is no cam-driven mechanical High Pressure Fuel Pump (a pair, one per each bank) nor common (per each bank) high pressure 'rail'.

That nuisance came later, with the "Gasoline Direct Injection" on the 5.0 V8.

At even a THIRD of that ten year ****-rot period of sitting on degrading fuel, AND the mileage on it, in general, I'd suggest:
- a new in-tank pump and filter/outlet
- new inline fuel fliter
- proper cleaning of injector & TBI plate ('manually - not by running Snake Sweat through the tank..)

....as a minimum.

At FAR less neglect (under 450 miles driven in three years. only 87 miles in 12-months, the most-recent year) & @ around 105K miles, I'm also replacing both left & right upstream & downstream Oxygen sensors - 2 each type - and the L&R cat converters.

Also a handful of other valves and sensors, some as called for by codes, others just on general principal of age / mileage, KNOWN abuse w/r the stale fuel, and/or often-mentioned reputation in the forum for going needy around the age & mileage on it.

Meanwhile, I've replaced some suspensions bits - both front air-struts, new WABCO compressor, the most costly.
Rear struts are still "to do" as the OEM's are not YET leaking, but "should be" and will 'any day, now', once I resume DRIVING it.

Chinese-made air struts let me retain the air-suspension system load-balancing and leveling functionality cheaply enough, but with "fixed', no longer "dynamic" shock absorbers. BFD... I also have a set of 'coil-overs' laid-by for all four corners to cover rapid/emergency repairs, if need be.

Nine-plus years with the XJ8-L, just over three since buying the Range Rover Sport, if I could change anything by just 'wishing'...

- I'd wish the X350 did NOT bleed-down its air struts after parking. There's one damn-fool design-flaw that I CAN correct cheaply..

- I'd wish the Rover L320 had the more reliable 4.2 TBI V8 rather than the fragile 5.0 GDI with its even WORSE cooling system Charlie-Fox collection off an already-dodgy assortment of design flaws.

Better yet, that BOTH had a typically 200,000+ -> 300,000 miles low/no maintenance Toyota, GMC, or MOPAR small block V8 instead of the AJ-hand-grenade that even Father FOMOCO abandoned long ago.

"At least one" GMC small-block transplant has been done.

If I was even thirty years younger, I'd be tempted to do one with a MOPAR.

 

Kinda sad the reputation the AJ-V8 gets because Jaguar can't seem to stay consistent on making timing components that just work. The 4.2 and 4.4 were peak AJ-V8 reliability-wise, but the 4.0 and 5.0 issues are what everyone thinks of.

A brief summary of the Jag AJ-V8s in NA for the uninitiated:

They had issues with the early 4.0L engines wearing through tensioners, so for the 4.2 and 4.4 variants, they over-built the crap out of the tensioners and those engines are extremely stout and reliable even with heavy neglect. They later added VVT, giving the cars a startup rattle with higher mileage that commonly gets mis-diagnosed as timing chain tensioner failure (both my XJR and LR3 have this issue at 153k and 244k miles respectively). Jaguar later dropped the ball again with the early 5.0 variants that once again had timing chain tensioner issues (they did revise the components later in around 2013, but that engine's reputation had been done in by that point).

 

hi Afaik
i did change the inline filter, now how do you clean the fuel injectors, do they have to come out ,texted and then put new filters in them?, thank you!

 

..had to make the best of a bad situation whilst owned by Ford. They got, summor of 1993, was it? A budget of Euro 200 million - 100 million of that for building a production faciilty, and the other 100 million Euro for costs of staffing, development, testing.

Good on 'em for getting into production fast and well.. but that was "small money" by that date. Very.

Ford left the game, Tata/JLR no longer budgetted enough for needed corrections, had to just 'get by' with minor patches to what they had whilst pivoting to the Chinese JV & market.

Soooooo.. we have a V8 that is overly prone to cooling system failure .. so fragile about it that it can become catastrophic failure in the proverbial "New York Minute"... and costs too much to repair or replace. Timing chain issue is the "other shoe" as gets dropped.

The "market" does wot it always does... 'adjusts' the value accordingly....

 

Are you quite sure that the fuel injector is giving you the problem? Grab a mechanic's stethoscope, and if you can hear the injector solenoid ticking while the engine is running, then the injector is likely working. A few years ago, I had a #3 cylinder misfire too, and it turned out to be the coil pack. This is what I suspect that you have.

 

Hi Rickkk
thank you for your reply, I do have a stescop, I will do that, do you know which cylinder 3 is,I am assuming the 2nd one to the right standing in front of the car and facing the motor.
also my 2nd question is, if the coil pack is bad, would the car starts?, thank you!

 

Odd cylinders on the AJ V8 are to the other side;

https://www.jaguarforums.com/forum/x...j8-4-2l-75948/

And, yes, an AJ V8 will start and run (restricted) with more than one coil-pack (or its connected wiring) faulty.

"Usually" the scanner will list the misfires both by specific cylinder and also "random misfire" and/or "..misfire detected at start up...".. but it retains and ADDS that info after a settling-in period to reduce false-positives... doesn't display it right away.

"Sometimes..." the proximal cause is coolant getting in from a failing head gasket and impairing combustion. "Tiny mind" knows it ASKED for a firing pulse, knock sensor didn't see one... throws the misfire flag.

Meanwhile, down the tubes, unburnt charge then causes the O2 sensor to lie, doen't do the cat converter any favours, either..and s**t rolls downhill, thereafter.

Dig DEEP and paranoidally, early-on.

If not caught and corrected earlier - and hopefully cheaplier - it will be corrected only costlier and rudelier, laterier.

DAMHIKT!

 

The No. 3 cylinder would be the 2nd one from the front, and to the left while standing in the front of the car and facing the motor (refer to the illustration). Actually, my 2005 Jaguar XJ8L would start every time with the defective coil pack at the No. 3 cylinder.

 

hi rickkk
thank you!

 

HI Termite
based on your reply, im sorry its overwhelming for me, and since you had mentioned the coolant, there is a message on the dashboard engine coolant low, and the coolant was low and it was below the minimum mark, so i added some coolant and topped the minimum mark, the message stayed, i added more and topped the maximum mark and the message stayed, the message still comes on when i drive the car, and i drive the car around town im almost done with the full gas tank that i had filled a month ago,it was the first fill after 10 years because the car was sitting,anyway i had drove the car couple weeks ago 30 miles one way, and while coming back home i had to pull to the side of the road and shutt the car off because the temperature gauge had raised all the way to the red, and then the first time i checked the cooler and it was fine waited 5 minutes then started the car the temperature was normal then proceeded driving then 6 or 7 minutes later the temperature gauge rises again , i pull to the side and shutt the car off, but this time i restarted the car in about one minute and the temperature was fine and i drove back home with no problems, so you know the engine coolant low message still on the dashboard till now.thank you!