As said earlier, I have never done the timing on a V6 Jag. However, going by all other engines I know of, there are clear markers for the position of the different components, when reassembling an engine. With cam belts and chains, it usually involves marks on the sprockets on top, relative to the mark on the the crank (pulley). A worn "stretched" chain on a 560 V8 Mercedes (as an engine I do know), can cause the cam mark on one bank to be on mark, yet the pulley be off by maybe 10 degrees. And that is just a result of wear, the holes in the links getting bigger, and the pins getting smaller. That chain has almost 100 links (96, I think!) so take a bit of wear for each link and multiply by 100..
If there has been a couple of teeth misaligned on one bank on assembly, you could lose power because spark might be happening too early, or too late on the compression stroke. The first could perhaps cause pinking or knocking (and possibly even a reaction to that if you have knock sensors), the latter increase in exhaust temperatures.
Two teeth might well be too little to bend valves, but certainly too much to retain performance or smoothness. The joker in the pack could be the automatic valve adjustment, if you have that on that engine.
But what can be done, even if there are no marks at all, is to use a degree wheel on the crank and then measure lift directly on the cams. And compare that to the position of the piston. If you assume the one bank is right, then compare the two. But I am convinced there are ways to ascertain the position of the cams that are easier, we either need a person who knows the procedure, or go and study the relevant literature, Preferably both!.
Then check.
Addendum: A short search throws up quite a number of results. It appears as if general confusion reins. Here is a thread from the X-type guys, I would assume! the engines are identical. It looks as if they confirm whatever procedure is shown in Haynes manuals: https://www.jaguarforums.com/forum/x...correct-32221/
If you have got it wrong, it seems you are not alone.

 

battery voltage fluctuation or issues ??? very good suggestion , thank you.. i will check voltage at other points at you are suggesting ,,,, I have notice early morning start car is the WORST .. IDLING ROUGH .. as the day progresses it seems to run better idling pretty good and also late afternoon yesterday I checked the torque on the top plenum bolts (suspicious of vacuum leak ) found all good ,, SMOKE TEST found NO leaks either. .. had the car parked in driveway after a while coming home and hot engine - MAN ENGINE sure sounded GREAT , no knocking noise at ALL ! . probably its why
i m .......KEEPING HOPE ALIVE !

this morning on my way to work rough start .. restricted performance came on / off five minutes later and codes.. BANK 2 too lean and multiple cylinder misfires..

as far as timing components and setting procedures goes / most of them new except guides .. timing setting - AGAIN i followed the procedure very closely on JTTS ( NOT stating that is NOT a possibility ) however.??
IF timing is off !! how come engine seems to drive pretty good after warm ups ? i know maybe a dumb questions these days I wish " a so called clown in chief leader " would ask more questions .. we would be in a better place ..

I m still waiting for new 02 sensors via rockauto ..

multa gracias to you ALL.

 

OK I’m coming in late but I’m here to help. I can solve this. I just need some baseline information and some tests to be run. Let’s start with the spark plugs. pull all eight plugs. number them so you know which cylinder they came from and take a picture of them. I want to see what they look like. If you have a bank Thats lean, you will see it. Spark plugs will tell you a lot about the way the vehicle is running.

Hopefully plugs will tell us a lot about what is going on but I have to start there because since you’ve had major issues you might have a bunch of plugs that are burnt to a crisp gaps are way out of line corroded whatever bad coils. I don’t know yet. Show me the plugs.

before you pull the plugs you might want to put your scanner on the car and watch the short term fuel trims and the voltage and current outputs of the bank one and bank two upstream and downstream sensors. Those signals should be trying to adjust to just above zero and just below zero and it will go back-and-forth as the car runs.
look for differences between the bank one sensor one and bank two sensor one and the differences between sensor two on both banks. Tell me what the maximum and minimum values are and post a screenshot of the signals.

You may have a smoked cat and that’s ****ing everything up but I need to know what your plans look like and then I need to see those signals that I just listed. a video would be great

When I took my supercharger off to replace my cooling hose the first time I put it back together I may have over torqued a bunch of the intake gaskets and flattened out several ridges which caused me minute vacuum leaks that would change as the engine heat it up. But I actually could see those using my smoke tester although it was almost impossible to see exactly where it was leaking from but I could see a small whisk of smoke you have to look very very carefully.

 

One more thought, about running a smoke test. Like nearly all tests, a smoke test is not always conclusive. Consider this:

The smoke test you did was probably good at checking the installation of the intake plenum and the intake manifold. However, there are some vacuum lines connected to the intake manifold. Some of those lines have check valves or shut-off valves. When you inject smoke into the manifold area, those check valves will automatically close. Same with any shut-off valves. Unless these shut-off valves are bypassed or somehow commanded to open, none of that smoke will get into those lines. So say you've got some vacuum-operated component with a big leak, but it's behind a check valve or shut-off valve. The smoke will never reach the component and thus no leak is ever indicated. To do a comprehensive smoke check, you've got to understand the vacuum system well and figure out how to get smoke out to the end of each branch, which is the opposite of normal flow.

For example, you could have a leak in the evap system. IIRC, the valve in this line remains closed until the engine is warmed up and above a certain RPM at cruise speed. A typical smoke test won't have any effect on a break in the line, as smoke never reaches the breach. You'd think you'd get a fault code for the evap system, but I vaguely remember the system is not tested until certain prerequisites are met. The other faults you're getting may be enough to inhibit a test of the evap system.

Can you please post a picture of the vacuum diagram found under the hood? I'd like to see how everything is routed, if there are any components that aren't reached by a simple smoke test.

 

Maybe we should first agree which engine we are talking about. If, as I think, a V6 then you are two plugs short! or long, depending which way we look at things!

 

Alrighty guys ! ,
I can DO all you guys are suggesting ,,

- take a picture of vacuum diagram under the hood, easy enough.
I agreed I could have a very small leak somewhere else , i will take the data numbers today before I start taking it Apart again ( wonder if I should wait till I replace the both up streams 02 sensor ???) - possibility that may help ...
I will take pictures of the spark plugs or may even DO a video and post it another thought ! - should I get a scoping camera to get in the Cats via 02 sensors opening .. will that give us an idea what they look like ???? I m leaning towards this area been the biggest ISSUE .

thanks again Guys-

I just pulled the data as foloows:

engine coolant temp 99 c
STFT BANK 1 2.3 %
LTFT BANK 1 -10.9$
STFT BANK 2 -4.7%
LTFT BANK2 10.9%
FUEL PRESSURE GAUGE 384 kpa
MASS AIR FLOW 6.36 g/s
OXYGEN SENSOR OUTPUT VOLTAGE (0.720V)
SHORT TERM FUEL TRIM (B1-S2) 1.6%
OXYGEN SENSOR OUTPUT VOLTAGE (0.640 V)
SHORT TERM FUEL TRIM ( B2-S2) 1.6%
EQUIVALENCE RATIO ( lambda ) ( B1-S1 1.022
OXYGEN SENSOR CURRENT (B1-S1) 0.15 ma
EQUIVALENCE RATIO (lambda) (B2-S1 ) 0.965
OXYGEN SENSOR CURRENT (B2-S1) 0.20 ma

 

 

Wow, I'd forgotten how simple the vacuum system is on these cars. Nothing like the bowl of spaghetti from the 80s.

Does it look like any of those three lines connect to a point that would mainly affect the suspect (#2?) bank? If so, that might be part of the equation. From the diagram, it kinda looks like the evap system (vapour mgmt) might fit the bill.

Scoping the cats won't hurt, but would you know what to look for? I sure don't. Maybe you can find some good pics online.

I'd suggest holding off on anything major until you can replace the O2 sensors. Your latest numbers still show a big split in LTFTs. I'm still willing to stake your reputation on at least one suspect O2 sensor (maybe both) plus some sort of mechanical problem such as a vacuum leak or cam timing.

 

One more long shot, after looking at that vacuum diagram.

Disconnect the vacuum line between the fuel pressure regulator and the manifold. Turn the key to Run but not Start. The idea is to energize the fuel pump but not consume any fuel.

Watch your scanner. The pump should run briefly to pressurize the injectors and then shut off. With the pump not running, the pressure should hold steady for several minutes.

If the pressure drops, look at the vacuum line for the presence of any fuel. This would indicate a regulator leaking fuel into this vacuum sensing line, and thus into the manifold. This would really mess with the air/fuel ratio. You’d see no external leakage, and a smoke test would pass with flying colors.

If no evidence of leakage at this line, yet the pressure drops, you have either a leaky injector(s) or a bad check valve in the fuel supply. A bad check valve wouldn’t really affect anything once the engine is started, so a leaky injector is more likely.

 

BINGO ! I think pressure started around 351 kpa dropped gradually to.............. 329 kpa before I turned off the key .. NO FUEL in line at ALL so It maybe time to look at injectors AGAIN ??

also I did get the 02 sensors today .. should I hold off on replacing them till I look at the injectors ?

WAIT A MINUTE ! just did the same procedure with vacuum line plugged in to pressure regulator I got the same result ??? I could also keep hearing the pump priming all this time while the key was "ON"

 

Don't forget Rick's famous pics..

 

That's normal, don't be alarmed. The only reason I had you disconnect that vacuum sense line was to check for the presence of fuel.

Just curious, have you experienced difficulty restarting the engine when it is still hot? Say if you stopped for just a couple of minutes to knock over a liquor store and then ran back out to the car? Trouble with hot restarts is a symptom of leaking injectors, so that would be a big clue. Also, if lots of cranking was required when the engine is cold. Normally the engine should fire up very quickly after you turn the key to start, no matter the temperature. You should never have to crank the starter on and on.

I did some searching, hoping to find official leak down specs for the fuel injectors, but didn't find anything. Does anybody know any official numbers? Just searching for "fuel injector leakdown test" or similar gave me all kinds of generic values for what is considered excessive leakage. This is probably the most informative article I found:

AGCO Automotive Repair Service - Baton Rouge, LA - Detailed Auto Topics - Fuel Pressure Tests for Hard Start

Please note that article mentions a mechanical gauge connected to the test port on the injector rail. 2003+ V6 engines don't have this handy test port, so we will have to rely on what your scanner sees from the pressure sensor on the fuel rail. Either that, or purchase an expensive adapter...

First things first, let's make sure your fuel pressure sensor is reasonably accurate. We have no real way of checking the accuracy at normal pressure, so we can only check it at zero. To bleed off all pressure from the injector rail, open your trunk and remove fuse F23. This should disable the fuel pump. Hook up your scanner to read the fuel pressure. Now try to start the engine, which will dump any residual pressure via the injectors. The engine may sputter, run for a couple of seconds at most, and then die due to zero fuel pressure. Don't turn off the key. Your scanner should show zero fuel pressure, or nearly so. If not, the sensor is inaccurate and must be replaced. Please remember this doesn't conclusively guarantee the sensor is accurate at normal operating pressure, but does confirm it is accurate at one point on the scale.

After testing the sensor like that, turn off the ignition and reinstall the fuse. Turn the key back to Run (not Start) and the pump should run briefly to pressurize the fuel rail. Record this pressure. Now start the engine. A little extra cranking may be required this time, and the engine may run roughly at first, so don't be alarmed. Once the engine smooths out, record the pressure again and then shut off the engine. Remove that same fuse again. This lets you keep the ignition on so the scanner works, but without any possibility of the pump running. Watch the pressure on your scanner and wait. How long? Well, I don't have a good answer. Wait at least 5 minutes, 10 or even 30 is better. Record the pressure after this waiting period and get back to us with the numbers and we can make an educated guess then.

The whole test procedure, other than the waiting part, should only take a few minutes. I'm just trying to think of any basics we should be covering before digging in more deeply, such as checking the cam timing.

 

before I move on to other troubleshooting procedures !!

got this issue now after doing the vacuum line to fuel pressure sensor check up .. and yea ! decided to replaced the 02 sensors with new ones just got from Rockauto : ULTRA-POWER2349030 (oem)
most of the time I get pretty decent stuff from them ,, if they don't work I can always remove them and put the old oem back ( I may have to do that now ) …????

NOW car is running worst ( no power lack of fuel transferring it feels) drove it a bit - I m getting P01646 code FUEL PUMP RELAY #2 .. so swapped two other relays ( same rating ) from front engine fuse box TO rear fuse boxe - R8 fuel release and R15 fuel pump relay - SAME RESULT ! I have also disconnected the battery charged it reset ECM .. same problem

guess I m thinking these two NEW 02 sensors are NOT working .. bummer 130 for both of them..

NO long cranking at starts - cold a bit longer once it warms up starts right up. / I also have a new fuel pressure sensor and I can DO the other troubleshooting procedure once I get oxygen sensors issue resolved !

thank you Karl.
I just swapped these new 02 with previous ones all back to normal- code p01646 deleted gone.... I will proceed and work on other procedure let you know how it goes
I think can rule out the 02 sensors - it ain't that !!

 

Okay, time for a rarely-used troubleshooting technique. Follow the instructions in this training video:


When you feel the dart hit, it only stings for a few seconds and then you will be overcome with a feeling of bliss. Do NOT pull out the dart. Trust me, it's for your own good.

After you wake up, first thing is to make amends for anything you did before the tranquilizer kicked in fully. Next, get a roll of opaque tape, such as duct tape or electrician's black tape. On the face of your scanner, apply at least one layer of opaque tape over the generic definition for any particular code you might retrieve. I'd suggest applying a second layer of tape in case the first falls off. Cover up the portion of the screen where your scanner defines P1646 as "FUEL PUMP RELAY #2".

Now, I'm assuming (Danger! Danger!) you meant P1646, not P01646, which is one too many digits. With the generic definition covered up on your scanner, go here for Jaguar-specific OBD codes. This is the ONLY place to interpret codes, not what your scanner thinks it means:

http://www.jagrepair.com/images/Auto..._OBD_II_R2.pdf


Note the definition for P1646, a fault in the heater circuit for Bank 1 upstream O2 sensor. Hmm, wasn't that one of the two parts you just changed? Way more likely than suddenly getting a new fault with non-existent control circuit for the non-existent #2 fuel pump on your car.

Sounds like you had the misfortune to get a new part bad out of the box. Bummer, but it happens. There's also the possibility the connector isn't fully seated, or the wiring got damaged during replacement. One step forward, two steps back. Unless you messed up the wiring, this one isn't your fault. Blame has been pre-assigned.

What to do next? Sell the car at a steep discount. How much do you want? Or you can swap the new sensors and see if the fault follows.

 

Ultra-Power is OEM? That's news to me.

I would recommend stop throwing NON-OEM parts at this vehicle. But wtf do I know.

 

Agree completely....post cat o2s look good as well as commanded lambda....i know you have put a lot of dollars in recently, but genuine pre cat o2s are a must....either denso or bosch....it should be one or the other...look at your originals....if not sure use a genuine jaguar parts reference like sng barrett or jagbits or classicjaguaruk.com

 

Was this a late edit to your post? I don't remember reading you had reinstalled the original O2 sensors and that took care of the new fault code. Be careful with edits like that. It makes it easy for us to miss important details. I was waiting for you to clean up the new code, and didn't realize you already had.

I'm still not convinced your old O2 sensors are both accurate. Are you still seeing a big split in LTFT? If so, and this split was 100% mechanical in nature (vacuum leak, bad injector, cam timing, etc.), you'd see no change swapping the two sensors. After swapping, each bank's reading would remain unchanged with equally accurate sensors.

You had a substantial change when swapping the sensors. That's a huge clue that at least one sensor is inaccurate, possibly both.

And to reiterate, you may also have some other issue at play, likely mechanical. Don't despair, you're making progress whether you realize it or not. Remember, you're still in the troubleshooting stage, not the fixing stage.

 

So late Friday afternoon I decided to " try an experiment " mad scientist here .. replaced all old 02 sensors ( ALL OF THEM ) with the NEW EBAY 02 SENSORS (4) ( cheap stuff around 70 for all of them ) SUPRISE SUPRISE ….
strangely car ran better than it ever has !!! Friday after several starts drove to GYM to walmart ,,,, ALL looking real good FUEL TRIMS both short term both banks staying around 0 ST bellow 10 LT GO figure,,,

Saturday morning - drove to airport to pick up my roommate , stopped at gas station filled up gas tank full , notice fuel leaking from underneath quite a bit then stopped .. guess I filled it too much (may have issues there NOT sure if that is related ort effecting the fuel distribution, its been raining today so I haven't a chance to pull the rear seats .. kept on road to airport all hell broke loose … restricted performance , multiple misfire cylinder codes . post catalic code .

I m pretty much ready to open it up AGAIN .. I m convinced NOW I got some issues injectors , timing or VCT solenoid issues .. its MECHANICAL ...

 

Me: