2003 XJ8 83,000 miles

Prior to it not starting 3-4 months ago I got a check engine light and ran a scan. Only two codes: Left and right banks running too rich. I understand that it probably means time for a change of the oxygen sensors. I was also getting the "restricted performance" message as well. Next I had multiple hard starts where the engine sputtering at start up. When this happened I revved the engine up to about 2000rpm and it would smooth out and run okay.

Then it just wouldn't start. I checked everything including fuel filter (changed), fuel pressure, compression, spark and spark plugs, injector pulse, etc..

Then I did the hard reset to drain the capacitors by touching the negative to the positive terminal with both terminals/cables not connected to the battery and VOILA !! it started immediately. YAY !!

I have driven the car about 3000 miles since then with intermittent check engine light, restricted performance message displaying. checked the codes; and the same left and right banks too rich. I was getting ready to go ahead and change the oxygen sensors, when the same set of circumstances happened again; sputtering at start up. Now not starting again.

I tried the hard reset again, but no luck


What does anyone think is going on and what would you suggest as next steps ? Whenever I am able to get it to start again, I'll immediately be changing the oxygen sensors. Duh...

HELP !!

 

Welcome jacksxj8....
I don't believe it will start until you get those O2's changed. Your O2's measure your exhaust and send info to the ECU, which is also receiving info from your MAF....it calculates those measurements to determine your fuel/air mixture. So, if either of your O2's is telling it you need too much fuel or air, ...that restriction of or too much of one will either flood it or choke it or if its toast, not send any signal.
I would check the plugs to see how wet/dry they are or aren't, check your gaps while there. If your gap is worn and too much, she won't run. I would not only suspect the O2's, but the MAF. If the MAF has gone south, she will not start either because the ECU can't calculate throttle draw. Check all connections for these areas, make sure they are locked and no broken wires.
Try doing some searches and read up on what others have run across and fixes for it. Use the search drop down in the task bar above, other than that, that info you retrieved last will be your source for repair. Your problem still exists from 3000 miles ago, it just limped along until now when it went from cracked to broke.

 

Thank you for replying.

I am convinced that the Prince of Darkness is not Ozzy Osborne, it's Jaguar electronics....

Let me see if I understand you.

The faulty O2 sensors are causing the too rich fuel mixture in both banks of cylinders. I understand that with my car having 83,000 miles and being 13 to 14 years old that they (the 02's) could be faulty and thereby causing this problem.

And then finally the ECU said, "No way I am starting until the 02's are changed...".

Okay, so if this is the fix, then how does the ECU recognize that the 02's are new (thus changing the air fuel mixture) and effecting a change instantaneously and so that the engine will start immediately ?

Before all of this happened I cleaned the MAF sensor about a year and a half ago.

And as in my Post, when I did the hard reboot the last time, it started immediately. Why do you think the hard reboot isn't solving the issue of starting this time around even though everything that has happened up until it not starting this time is identical to when it wouldn't start last time ?

Finally do the dealers have scan/test equipment that can accurately pinpoint the problem ? I just have a code reader which is how I know the two banks of cylinders are running to rich.

Thanks much !

 

I'm not saying its the fix, your codes are and that's where you need to start. Check the connections for corrosion and such. If the MAF is bad and sending bogus info, it can cause the rich condition and flood the ECU with bad info and prevent it starting...then again, maybe not. That's why I asked you to check your plugs also, it could be a combo of small issues and seem like something else.
Its the collection points that you mainly need to check....O2's, TPS, MAF and MAP to start with. The car said check my O2's, so that's where I'd start. Any breaks/corrosion in the electrical lines or cracks in vacuum lines can send the wrong signal to the ECU via the information collectors, even though the info collector may be good.
The ECU is constantly monitoring its sensors for faults, when you have a fault and replace it with a new part, it will recognize the fault is not there and should reset via using your scan tool.
Your previous reset... and it starting... was probably the result of a failing (not failed) part. Resetting it only delayed the inevitable of total failure, it worked just enough to hide it from sending a code. Kind of like a tire with a slow leak not totally flat yet.
The dealers have all sorts of neat expensive deep scan tools that cost $$$$, that can read things a standard code reader can't. That's why there are folks like motorcarman, Plums, Bob Goff and the like, who use these devices for their work. But to prevent paying them such $$$$ rates is why your here and to try the simpler methods first (usually the answer) and save that cash. These guys are also kind enough to give their advice to assist you.
I guarantee I will not be the only one to respond with other answers to help....give others time to get here to read this and see what they say. There are people from around the planet who respond....Australia, England, Taiwan, etc...who have dealt with your same scenario.

 

Apologies for not being clearer.

Thank you

There were only two codes. One for left bank too rich, and one for right bank too rich.

My assumption (from listening to a few folks out there in auto enthusiast land) was that the 02 sensors were most likely the culprit. There is a person here on the Jaguar Forum who is a Jag mechanic in southwest Houston (Brutal is his user name).

I contacted him directly thru Facebook. His thought is the fuel pressure regulator versus the 02 sensors.

Just before contacting Brutal, one of the things I tried just to get it started was to press the accelerator pedal to the floor and see if I could get it to start that way. Probably just flooded it.

SOOOoooooo first step is to take a look at the spark plugs and see what's what. I will also check for spark (as I did 3 months ago).

With the conditions I have now described and listening to Brutal, I'll replace one bank of spark plugs (was getting ready to do all 8 anyway) and squirt a bit of oil into the same 4 cylinders as I may have washed the cylinders with gasoline. So if it starts (or even if it doesn't) then I'm going to replace the fuel pressure regulator first, which is easier and cheaper than purchasing two O2 sensors.

Then if it starts, or even it started after only replacing 4 plugs and squirting oil, I'll most likely replace the O2 sensors too.

I'll keep you posted.

Thanks !

 

By pressing the pedal to the floor you actually shut the fuel off rather than flood it. As to the O2 sensors, the ECU starts the car in open loop, with a preset mixture. The O2 sensors function when the engine heats up and the ECU switches to closed loop.

I think the MAFS could be a problem when starting, but the possibility of bore wash needs to be eliminated first.

 

Yep. Gonna check the bore wash first.

But today I'm gonna take a break until tomorrow because the car is outside, covered with a thin coating of ice, and it's 21 degrees. I'm northwest of Clarksville, TN.

You may be correct in that there was not a gas smell coming from the engine bay after I tried the press the accelerator to the floor method (more like 80% down) and attempted to start it. It almost started, but not quite. Similar experience to what one gets when one is out of gas, or almost completely out, and one is thinking "Come on baby start, you can do it...."

As for today, there is football, etc.. Then tomorrow it will be warmer and I'll hopefully eliminate a few things and it will start.

Will check back tomorrow.

Later on Wayne, I mean High Horse....

 

Pushing the pedal most of the way will not shut the fuel off. The owners manual covers starting from a bore wash but doesn't call it that. The procedure is to to floor the pedal, crank in short bursts (which will put oil on the cylinder walls), then lift pedal part way to start.

 

Both O2 sensors don't normally fail at the same time so did both rich codes appear at the same time and never before? If so, I can't see O2s as the cause.

The hard reset clears the learned fuelling etc tweaks, and may have helped with starting.

If you suddenly got codes for both sides rich you're probably looking for a cause common to both sides (MAF, fuel pump or whatever).

 

Hey Veteran Member,

Thanks for the feedback.

Back in the late Summer when I did the hard re-boot, I had checked everything: Fuel filter (replaced), fuel pressure checked okay with a gauge off the fuel rail schrader valve, injectors were pulsing okay, had spark and spark plugs looked okay.

So on the advice of this Forum, and my local mechanic I did the hard re-boot by touching the negative to the positive with both terminals detached from the battery, and PRESTO !! it started.

This was all 3 months ago, and I have only driven 2000 to 3000 miles since then with the check engine light and the restricted performance message coming on intermittently.

I was getting ready to do the oxygen sensors, when the sputtering starts began as they did in the late Summer, leading to it not starting at all.

SOooo the prevailing feedback here on the Forum, and from a Jag mechanic not on this thread, but a Forum Member (named Brutal) is to start by looking at bore wash due to attempting the to start it using the "press the accelerator to the floor".

As far as codes, yes, both codes appeared at the same time, one for the left bank (too rich), and one for the right bank (too rich).

To begin with, I'm going to replace the plugs on the drivers side (and later after I affect a start the passenger side as well). I will squirt some oil in the 4 cylinders where I'm first replacing the plugs to ensure compression on that side, and then se if I get a start.

None of what I have just written thus solves the core problem of what created the problem of sputtering starts and then no start with the codes I have.

Brutal recommends looking to the fuel pressure regulator as the possible culprit, so if I don't get a start with replacing the first 4 plugs (or even if I do), that is what I am going to replace first, simply because it's easier, faster, and cheaper than 2 oxygen sensors.

Then I'll see what I have with it starting, and even if it has started previously with the first 4 plugs, I'll be looking to solve the core problem of both cylinder banks running too rich.

SOoooo if I have it started with this step, then I'm replacing the other 4 plugs anyway.

The plugs are the original plugs, and the car has 83,000 miles, plus it's a 2003 model making it overdue for a plug change. Duh.....

I changed out the air filter for a new one, and cleaned the MAF sensor a year and a half ago. I only drive this car about 13,000 miles per year.

So after this if I still have a no start situation, I'll look into checking the Throttle Positioning Sensor, then the Manifold Absolute Pressure Sensor, and finally the upstream O2 Sensors, and of course hoping for a start after each step. And if it should start after each of these steps, looking for the codes to clear, or re-setting the ECU clear the codes to seeing if they come back.

After saying all of this, if you read my initial Post, I am convinced that Jaguar electronics are the Prince of Darkness, and not Ozzy Osborne.... Bha ha ha ha ha ha....

And, here's the funny thing, back in 1964 my father, who was a physician, bought a brand new E Type. Within a year, while he was driving between hospitals, it caught fire and burned to the ground.

I think these cars, with all of the sensors, are WAY, WAY over engineered.

 

I seriously doubt you have a bore wash problem: not likely in a 2003; rarely seen in US with current low sulfur gasoline.

Make absolutely sure your battery cables are tight. Check that there is energy at the false bulkhead connectors (Googe it); check that your MAF sensor plug is in tight with straight prongs; check your temperature sensors is providing correct sensor reading (if it is not telling the ECU that it is cold out, the ECU does not enrich the starting mixture).

And what are the actual P codes you are seeing?

Finally, try shooting a jet of starting fluid into the throttle bore. If it starts, my bet would be the temp sensor. While it is running put some SeaFoam or such into a tank of gas and clean up those dirty injectors.

 

Hey J Hartz-

Thanks for the feedback.

The actual codes are PO 172 left bank too rich; and PO 175 right bank too rich.

Overall and obviously, different sensors individually or combined, can cause these codes to occur, and to occur to the point that the car doesn't start.

I really hate that this car, with an original window sticker of $56,000, does not have a fuel delivery/spark/ignition system that can fail in this way and isn't more reliable.

It's as if Jaguar (owned by Ford at the time) designed (on purpose) a car that would fail in this way so that the owner would have to come into the dealership to have the problem pinpointed and then repaired -at an extremely high labor rate.

Yes, I know that large percentage of the profit margin at a car dealership is made in Service and Parts, and that's okay with me.

But Toyota, Honda, Nissan, etc (brands considered more reliable) have the same model for their dealerships (which again is fine with me), and their cars hold their value better, their dealerships are successful, and they don't break down as frequently.

I just wish Jaguar (during the Ford years) had improved the electronics more than what was achieved.

And now on to the repair....

Tomorrow (Wednesday) it will finally be warm enough to go out and do what I need to do to get this wonderful XJ8 back to running and driving again. I am the second owner and bought the car almost 3 years ago with 45,000 miles. It now has 83,000 miles.

The spark plugs have never been changed, and so that is the first order of business, and I'll be squirting the appropriate amount of oil into each cylinder to eliminate bore wash as a symptom -even though I know that is NOT the root cause of the problem of not starting. A Jag mechanic stated it might be an issue because I attempted to at least start it by pressing the accelerator to the floor (even though some on this thread say that doing that may actually caused the ECU not to inject any fuel for obvious reasons). The Jag mechanic also knows that this is NOT the root cause of the problem of not starting.

He suspects the Fuel Pressure Regulator versus the upstream 02 sensors.

Aye, and there's the rub.....

One doesn't really know what will cause the problem of the non start, and both banks of cylinders running too richly, because the problem of it not starting combined with the two codes I have, can come from any number of sensors individually (or a combination) and then what the ECU does with that information. Gotta love it

If I could wave a magic wand, right when the "It Won't Start" problem occurred, I would hook up the Jaguar dealer's diagnostic system to my car, pinpoint the problem, repair it, and be on my way because we all know that in addition to knowing that both banks of cylinders are running too rich, I would also know why as well.

Yeeeeeee Hawwwwwww

 

You appear not to realise that Jaguar/Ford DID vastly improve things and what you have is a specific fairly rare fault.

You could have the same issue on any of the ones you mention (and your laws require the same codes).

Still, perhaps YOUR best fix is to change cars.

 

JagV8-

Nope, I have never had an electronic issues like these with multiple Nissans over the years. None Same for other brands from various continents.

In fact two Maxima's I owned I ran the mileage up and over 400,000 miles during 15 years of ownership.. The only issues were to be expected; several alternator's and one starter, plus the usual tune-ups and brake pads.

Everyone knows that Jag quality is much worse than Lexus, Mercedes, BMW, Infinity --in other words, other luxury brands that are their competition.

Indeed since the late 1950's and early 1960's the electrical systems were horrible, and the cars were known to catch fire and burn to the ground. My father's one year old E Type did this exact thing in 1964.

I was hopeful that with Ford ownership, things would improve, and maybe they did. But the fact remains that Jaguar's depreciate faster (steep curve) and much more iverall than the competition. The legacy of poor electrical/electronic quality follows them to this day, as evidenced by same. So even if quality is better, the depreciation curve remains the same.

Having said all that, perhaps ownership by TATA will continue to improve things, but that won't be known for a very long time. Hell, if one currently owns 2 Jaguar's one could say, "Hey, you guys want to come over and check out my tata's.....".

I enjoy driving the car, I just wish the electronic systems were of better quality. I enjoy a few problems with the cars I drive, just not to the extent that this one. A few problems keep it interesting.

SOooo silly person, it wasn't an indictment, it was just the facts.

I do not know what you mean by "your laws require the same codes". You can explain that one to me. or not. Your choice....

Oh, and one other thing; I already own multiple brands of cars and enjoy them all for different reasons.

 

Some/most of those cars would not have had to meet recent emissions laws so you also could not get these issues...

By laws I mean ... well, laws. You have a government etc. They pass laws. The OBD-related ones require the same behaviour on all (petrol) cars. So you may as well get used to codes like P0172 (it's a 0 not O).

 

I feel sorry for ur problem, and hope you will be able to solve it.
On the above, have a look at any Benz or BMW forum and read some on models of ~2000.
The Benz 500SL as just an example ....
You will be glad you have a x308!
​​​​​​
Reality is, after some 15 years, some come as well maintained, and some as crappy ones.
But besides of some fundemental issues (and even for those I got some understanding), these cars are pretty rock solid, and with a surplus of very reasonable 2nd hand parts for most where needed.

 

Eric Jansen-

Don't feel sorry for my problem, feel sorry for Jaguar's problem.

I bought this car (2003 XJ8) almost three years ago with 45,000 miles and I am enjoying it. And I expected some quirks, which was and is no big deal.

One of the reasons that allowed to purchase this beautiful silver XJ8 with oatmeal leather at such a good price, is the same reason that is causing me to have to do the repair I am doing now.

What do I mean by this ?

That since Jaguar cars depreciate more rapidly and more overall than their competitor's due to the electronics issues and the legacy of poor quality, this fact allowed me to purchase the car at a favorable price. The other side of that coin is that I'm now dealing with these same attributes as the reason for the repair.

It's currently not that big of a deal, and I hope it doesn't become one. The interesting thing to me has been the learning curve and knowledge gained.

It is interesting that any number if electrical items (only non-electrical item not eliminated is the fuel pressure regulator) individually, or in combination, can cause a non-start to be issued/created by the ECU. It seems the ECU mostly does this to protect the engine from it's owner.

So I'll start by replacing all 8 spark plugs, and squirting a small amount of oil into each cylinder as I install each plug (even though bore wash shouldn't be a problem). And then, even if it starts, I'm going to drive the 80 miles to the dealer that is closest to me and have them do a thorough pinpointed diagnostic, so I will know if I need to replace any other electronic components like the TPS, O2 sensors, MAF (or just clean it again), MAP sensor, or perhaps the fuel pressure regulator. And of course any vacuum leaks with the intake manifold.

The rest of the fuel delivery system has checked okay; fuel pressure is within range, fuel filter replaced, and fuel pump is obviously working. Also, fuel injectors were checked to ensure they were pulsing and they are.

So here I go; out to the garage.....

 

jacksxj8, I see your in TX....motorcarman is in Decatur and a certified tech. I don't know how close you are to him, but he is very well versed and experienced. You may want to look him up if your close.

 

5 days since last heard: did you get it to start yet?

 

Hi, Highhorse, In "jacksxj8's" earlier posts he said "I'm northwest of Clarksville, TN." it was before X-Mas so he may have been visiting, or not, but hope he did get that non-start fixed....got me wondering about it now....lol