2004 XJ8 88k Miles - 1,400 Dollar Mystery Car
 

Does anyone on the forum have access to Jaguar factory build data??? Can I offer a Starbucks gift card to help me do some serial number research? I'm sure I can get the original serial numbers for the engine and trans from my local Jag dealer to but I'm really curious if I have a serial number from a random used motor (aka the used engine likely installed my mystery car), is it possible to do a reverse search in the system and find the VIN of the donor vehicle? A quick google search of the donor vehicle VIN might tell me how many miles were on the car when it died.

Back Story:
I purchased a mysterious non-running 2004 XJ8 in Troy, NY last week showing 88,244 original miles for 1400 bucks. The body and interior are flawless, no evidence of damage or collision repairs. Zircon blue paint is consistent, no color mismatch or anything unusual. CARFAX appears clean showing ~86k at the time of registration in the seller's name in 2014. The seller gave me his purchase documents from 2014 including a bill of sale showing that he paid just under 10k for the vehicle at a local used car lot. He had a large loan on the car that was paid off in late 2017 and I was able to use his title with his original lien release letter to get a clean NJ title issued in my name.

Here is where the mystery comes into play... when I purchased the vehicle I found ~75 DTC codes on various systems throughout the car. Owner claims it went into limp mode while driving and he had it towed to his friend's local repair shop where it sat for almost two years untouched while he paid off the loan. It was stuck in limp mode and the transmission would not shift into gear. Over the past week I've dissected the car and it appears that the engine was swapped by a poorly trained ape. Literally everything under the hood is either broken, displaced, disconnected or missing altogether.

The list is so long it is beyond recounting but just a few notable examples include:
- Right bank knock sensor pigtail jammed between the engine and transmission when they were bolted together, found ground up pieces of the plastic connector falling out of the bell housing.
- Left bank knock sensor plugged into the fuel rail pressure harness connector for some crazy reason
- Several loose bolts left in the valley of the motor
- Fuel pressure sensor not connected
- MAP sensor not connected
- Brake master cylinder vacuum line snapped off at manifold
- Intake air temp sensor not connected
- Front impact sensor crushed in half (ape used it as a knee pad)
- Both electronic throttle connectors disconnected / totally destroyed
- Original knock sensor harness connectors simply snipped off (extra parts of course)
- Transmission lines were ripped from their clips, bent and twisted to force fit into the radiator and then rapidly hack-sawed in half by the serpentine belt upon startup.
- Front of the engine / bay covered in the entire contents of the transmission sump as the serpentine belt acted like a transmission oil slinger as it slowly amputated the cooler lines.
- Rack & pinion solenoid broken off by twisted transmission lines.
- Intake resonator completely broken off of the duct (wide open air leak bypassing MAF)
- EGR gaskets missing

- etc. etc. etc.

After temporarily restoring all of the critical engine sensors, a quick intake re-seal and a few band-aid vacuum repairs I am left with nasty rattling noises coming from the bell housing, cylinder 8 and cylinder 3 misfire, oxygen sensor controller fault, transmission CAN link fault and the variable steering solenoid fault. Not bad transitioning from almost 75 faults to 5 faults with a week's worth of effort. If I can prove that the engine is viable I will lift it out and repeat the installation job properly with proper repairs and factory gaskets.

The question is who could be so heartless as to destroy this beautiful car? Remarkably the air suspension works perfectly and the CARFAX shows the struts were replaced at a Jag dealer 25k miles ago.

Kinda like finding, an available, single, as well as beautiful woman.
Without knowing anything about what her past is.
You could be real lucky, get just what your looking for.
With a little love, effort, & understanding, your both very happy.
Maybe not!!!
Good Luck

Haha, it's funny, my wife doesn't see the car project that way.

BTW we actually put the Jag in her name... at least now I can tell her I need to work on HER car.

Good move;:icon_crackup:

I'm taking it you still have the knock sensor codes. This for sure would put the car in limp mode.

Track each harness and if the connector is broken solder on a 200K ohm connector on the end of each of the knock sensor connectors.

This will trick the ECM in seeing a constant 200 ohm reading from each KS sensor harness, meaning "life is good in knock sensor land".

At least you can write off the knock sensors until you can get them properly hooked up (and replaced with connectors)

PM me - I'll gladly mail you 2 of these to use as I have about 18 left...

Knock sensors are fine. I just have a cylinder 8 misfire, cylinder 3 misfire, O2 sensor controller fault and a transmission CAN link fault. I have everything else cleared. I'm fine on the diagnostic end of things. I'm looking for someone who works at a Jag dealer who can run my VIN and give me my engine and transmission serial numbers. Further I'd like to do a reverse lookup on my engine serial and figure out the VIN number of the car it originally came from.

You've been busy, nice progress keep it up & you'll have a nice car when finished.
It is sad the way so many become just cheap used cars.

So just a quick update... After a lot of diagnostic work I'm a bit stumped. I spent all day Saturday investigating engine internals and timing, hand cranking and pumping air into each cylinder to see if the valve action agrees with the piston stroke. My intake valves are open on the intake stroke, exhaust opens on the exhaust stroke and at top dead center the valves are sealed tight and I can apply 150psi with very little blow-by noted in the crankcase. Internally the engine seems pretty solid but it still has a multiple cylinder misfire. I have a strong spark on all eight cylinders, I tested each coil with a light AND a spark plug to verify. Fuel rail pressure stands at 58psi at idle which is in line with my previous 2004.

I determined that my O2 sensor fault is the result of two wires stripped out of the left bank upstream sensor harness connector under the car. Both bare broken wires were shorted to the chassis. I carefully positioned the wires away from the chassis and my fault transitioned to an "open circuit" code. I've ordered new Sumitomo terminal pins from Ballenger Motorsports and I'll re-pin the harness connector when they arrive. Hopefully the O2 sensor driver circuit in the ECU isn't damaged.

With the left bank upstream O2 sensor disconnected I would expect an SES light and a bit of a choppy idle but I can't imagine it would throw the controller into limp mode and bring me down to four cylinders.

After pulling the fuel rail and visually inspecting the injectors I sprayed everything out with some brake clean and swapped injectors for cylinders 3 and 8 to 1 and 2. At first it seemed like my misfire fault moved with the injectors and I got excited but then I popped another code for cylinder 3. Misfire codes seem random.

I'll probably end up bench testing each injector and I may try to run them through my ultrasonic cleaner while pulsing each one open. I need to hook up my o-scope and take a look at a few more things before I zero in on the injectors.

Compression Test (dry and wet)?

Yes, sorry I should have reported... Dry compression cranking in clear flood mode with all other plugs installed shows ~150 psi across the board. I didn't mention my compression test saga. Some years ago I purchased a really nice Mityvac digital compression test kit. Compression was the first thing I checked on the Jag engine last week and I was showing about 46 psi on both banks using the Mityvac gauge. Assuming I had lost timing I proceeded to do my favorite home brew air injection test to see if I could figure out where the compression was being lost. As I hand cranked the engine through several rotations I realized the timing felt correct. I did a final verification where I hand cranked to top dead center on cylinder 1 in it's compression stroke. I unscrewed my air hose from the spark plug hole, dropped a dowel into the cylinder and hand cranked until I was absolutely confident I hit TDC (based on the dowel motion; I didn't bother using my dial indicator.) I then screwed my compressed air hose back into the spark plug bore and ran my regulated air pressure up to 150psi. I hardly ever perform a formal leak-down test because I find it is hard to rule out variables that can influence the results but I typically do a "qualitative" leak-down test where I check the cooling system for bubbles and pull a PCV hose to get a sense of blow-by from one cylinder to the next. The engine seems really tight compared to my previous 2004. I really didn't feel much of anything flowing out of the crank case... just a little hint of air. My previous 165k 2004 produced enough blow-by to play a musical instrument. Bottom line is that I didn't detect anything that would cause a multi cylinder misfire.

Just for fun I pulled a spark plug on one of my other cars and tested compression with the Mityvac gauge and got the same ridiculous readings. Oddly enough when the gauge is subjected to a constant pressure from the air compressor it is accurate. It seems that 15 years of sitting in the garage has slowed the digital gauge's response time and it can't see the pressure peaks anymore. I ended up checking compression on the jag with an analog pressure gauge.

Last night I restored the electrical connection to the bank 2 upstream oxygen sensor by temporarily soldering pigtails to the back of the connector terminals. The broken half of the connector is the vehicle harness side so I pulled the O2 sensor out of the catalytic converter and extracted the mating terminals from its intact connector. I carefully soldered a couple wires to the crimped terminals and pushed them back into the connector body. After reinstalling the O2 sensor I just soldered my pigtail leads to the broken wires on the vehicle harness which restored the electrical connection without sacrificing the connector body. Once my terminals arrive from Ballenger I'll do a proper re-pin repair on the vehicle harness.

Restoring the O2 sensor cleared the last of my mystery DTC's. Interestingly after shuffling the fuel injectors, my consistent misfire code has moved. I'm now showing a constant misfire on Cylinder 1 and an intermittent miss on Cylinder 3.

Bringing the bank 2 upstream O2 sensor back to the party has restored closed loop mode after startup. My cumulative fuel trim (short + long) on both banks is running ~19%. So I'm basically zeroing in on an injector problem. I've got spark, compression, and excellent fuel rail pressure. Shuffling injectors changed the misfiring cylinder and I can see the computer is sensing a lean condition.

Next step is to pull the injectors and throw them in my ultrasonic cleaner. I'll pulse each injector until I see cleaning fluid back-flushing and I'll check the spray pattern by simply extending the fuel rail hose away from the vehicle. I can just apply fuel pressure to a single injector and manually pulse it to observe the spray pattern.

Hopefully I'll have a smooth idle by Sunday. Once I clear the misfire concern I'll tear everything back down, perform proper wire harness repairs, restore the transmission cooler lines, AC lines and engine mounts. I'll lift the motor, possibly unbolt from the transmission and make sure everything is set back in place properly.

Quick Update... I built a variable frequency / variable duty cycle square wave generator circuit that allowed me to safely operate my fuel injectors on the bench. I placed each injector in an ultrasonic cleaner and activated them at ~25Hz / 75% duty cycle for 8 minutes each. Cleaning the injectors cleared a random misfire on two cylinders and vastly improved the idle quality. Replacing coils on another two cleared constant misfires.

Long story short, I now have a smooth running engine, with no stumble at idle! It seems like the engine is viable after all. Now I just need to see if I can find a "band aid" solution to patch together a transmission cooler line so that I can check the operation of the transmission before investing in proper fluid, filter and new OEM lines.

I also need to investigate a transmission CAN circuit fault and a weird rattle / grinding noise occasionally present in the bell housing area.