Ok so Ive owned this 98 xj8 for about a month now and when I met the guy to purchase it I found him sitting in the car looking pretty lost. He said the car is fine now, but a minute ago it would not start. I fired it up a few times and it did just fine so I just figured the guy didn't unlock the wheel or turn the key far enough.....I was wrong.
Yesterday thecar starts in the am just fine, gets me home for lunch and back just fine and then 4 hrs later I try to leave work and it just cranks and tries to start but its getting no fire at all(from the sound of it). The starter is turning just fine and it does not sound like the flywheel is missing anyteeth, it sounds fine just never runs. So I continue to try even 2-3 minutes for a few seconds and after about 5 tries aybe 15 minutes) it fires right up and rund fine. Today it is like it never happened.
So any ideas on whats happening? No fuel or no spark should be the answer, but its hard to tell with an intermitten problem.
Help would be greatly appreciated.
Thanks

 

has anyone else experienced this once in a while no start?

 

There are a couple of posts I have read in the past which might relate to yours. Both were fuel pump connection failures that were preceded by difficult cold starting symptoms, until the day came when the car wouldn't start at all.

The specific problem is that the negative terminal connection for the fuel pump link lead to the fuel pump, inside the tank, develops high resistance due to heat degredation. The plastic connector housing actually melts, the male spade terminal on the pump isburned black, and the female connector on the link lead is black and deteriorated.

I have seen this onXJ8's that were towed in for no-start conditions, but have not had a case myself where the fault was intermittant before it became...uh... terminal. It's logical to assume that the deterioration couldcause an intermittant connection before it goes open circuit entirely.

The reason I'm pointing this out as a possible cause relates to your description as "tries to start": that's the sort of symptom that occurs when an engine has enough fuel pressure retained in the rail to run momentarily, but dies soon after if there is no pump operation. Ignition system and injector operation are normal, so it starts on the first try but not the second.

None of the cases I have seen or inquired about have resulted in a diagnostic trouble code to be logged. Presumably the problem is caused by excessive amperage drawof the pump, and that the wiregauge of the terminal connection is sufficient enough to handle normal draw but loses the battle when the pump asks for more. The draw does not exceedthe amperage rating of the fuel pump fuse, so the fuse doesn't blow. Over time, the connection just cooks.

There is a shraeder valve on the fuel rail for pressure testing. I believe you can depress the center pintile to check for pressure, I have never tried to test that way as I have a fuel pressure gauge to screw onto the valve which does this safely.On the next no-start event, you could try wrapping a rag around the valve and carefully depressing the pin, and you'll get a nice squirt if you have pressure in the fuel rail. I'm not real hot on the idea, here's the way I would test it :

If someone is around to turn the key for you,go back in the trunk and listen for the pump running when theignition is turned on. The pump only runs for 1-2 seconds, it's not very loud, and emits a high pitched whine like a dentist's drill. You're listening at the forward wall of the trunk compartment, the tank is right behind the carpet.

Ifno one is around to help,here's what works for me: disconnect the negative battery terminal, turn the ignition key on, then listen as you reconnect the battery. The pump relay will immediately activate and turn the pump on for the same short period.

The hope is that you won't hear anything, since you caught the problem when it was evident. You should hear the fuel pump relay in the fusebox click on and then off, and the relay could in fact be the cause of the problem. All of the fusebox relays are the same, so you can interchange them.

One other suspect that comes to mind is the EMS relay, that is located beneath the cover that houses the engine and transmission control modules. These relays were upgraded, there's an old bulletin about the subject. A failing EMS relay would result in no injector operation, but that's not real easy to detect unless you have a stethoscope handy when you get stuck.

Crank sensor, ignition module, and ECM failures might come up often in discussions like this, but all have a very low incidence of failure. Maybe the best place to start is making sure you have the updated EMS relay, I'll track down the I.D numbers on the updatedrelay and you can compare yours. I'd probably replace it either way, and see if that doesn't do the job. I wouldn't change the pump relay if it were mine, you're better off waiting until you can catch it in the act and then know for sure what the problem was.

As you recognize, thisproblem won't be easy to find until it gets worse. There are a myriad of possibilities, and my mention of the fuel pump link lead is just a guess...but now you can test to see if that is the culprit. Regardless, please post any additional information you might acquire about other symptoms, or about what the cause turns out to be. I come here to learn too.

 

Hey Thanks Alot!
You really know your stuff and I will be sure to test it that why. I do understand the danger of the pressurized fuel rail, I have done my share of work on cars in general.
Thanks again, your a great part of this forum for help you have given.

 

Well I read your post at lunch today and when I got back to work and tried to come home....nothin'. It started for a couple seconds and had no throttle response, it just spit and sputtered until it died. I did this about 4 times hoping it would fire up and run right, but it got to the point where it would not start at all (battery is still good, it turns over just fine)
So the first thing I try is the valve on the fuel rail....a small puff of air and nothing else. I then get caveman-itis and kick the hell out of the fuel tank(with carpet pulled back so I dont kick something important) hopeing to jolt the pump or connection into working again so I can get home, but the neanderthal method didn't work out.
I switched the fuel pump relay with the stop light relay and still no start and no building of pressure on the fuel rail, so now I guess I switch out the EMS relay just for fun and see what happens.
The EMS relay issue should not leave the fuel rail without pressure should it? If the pump is working and the EMS has disabled the injectors or whatever else it does then the pump should still have pressurized the lines, correct?
I'll check back here later tonight when I give up.

Any body else have any guess?
JagtechOhio, again thanks for your ideas!

 

The cave man tactic isn't all bad, sometimes on XJ40/ XJS (same setup) I have tugged on the wires outside the tank and magc happened inside the tank.

I'm giving you a call, I need to know if you hear the pump relay click.

 

Two corrections to make:

My mistake, the EMS relay is located in the (small) EMS fusebox at the left fender well. The fuel injection relay is the one I misidentified, that is on the right side beneath the cover for the engine control module. The fuel injection relay is in the second socket, reading left to right. The first socket will be vacant on a normally aspirated car, it is for the intercooler pump on S/C vehicles.

Jaguar's mistake, in TSB 303-55. This bulletin is a lengthy fault tree for diagnosing no-start and hard-start conditions on AJ26 engines ('97-'98 V8).I was reading it again tonight and in the Symptom Matrix they indicate that a faulty EMS relay will cause a NO CRANK condition. Didn't make sense to me, and my '98 XJ8 cranked just fine ( but obviously wouldn't start) when I went outside and pulled my EMS relay.

As for the relays themselves, all of the light brown colored relays are part #LJA 6703AA. This relay is used for many accessory circuits, and for a few vital ones. On top of each relay is a date stamp, it's in white ink:

R6K1 through R6K8 is early issue.
2AB and subequent are updated relays.

The fault tree indicates that any early issue relay encountered during fault tracing should be replaced, period. That means Starter relay (no crank), Ignition coil power (no spark) EMS relay (I think no spark, no fuel, no injector pulse) Fuel injection relay (no injector pulse), Fuel pump relay (no fuel) and Throttle motor power relay (I'll check on this too, I'm guessing momentarystart and stall). Help me out if I missed any othervital ones.

Four of this group are under the cover for the Engine control module: the fifth one at this locationis for the A/C compressor clutch. First one in the row of six is the S/C intercooler pump relay.

The fuel pump relay is in the trunk fusebox. Following is a crude map of its location, I think FactoryJagTech posted this before:

R
R P1 R R
P2

Each of the letters represents a relay, P1 is the only fuel pump relay on a normally aspirated car and P2 fills the empty socket if the car is supercharged, for the additional fuel pump. The others are accessories not relevant to getting stuck in a parking lot.

None of the above is new information as of '02, andothers more experienced than I probably have it all committed to memory.Some ownersmight not have ready access to the information, so there you go.

As for Jim (XJ ate), I just got off the phone with him when his tow truck arrived. His '98 XJ8 was a crank but no-start, and he used my test to find that his fuel pump relay was energizing, but he had no fuel pump operation when reconecting the battery with the ignition on. Fortunately he had access to a testlight, and confirmed voltage at the connectionon top of the tank for the pump...time for the tank to come out, but at least we know it's for the right reason.

Fuel pump failures is nothing nothing new either, andI remember reading (I think it was BRUTAL) a post abouta burned link lead here recently.If you wish, click below formy webpage, I posted some photos of this problem when I first became aware of it. So this might be common knowledge to dealer techs, but Ihave not seenany published info on the issue. Intermittent no-starts, and perhaps other driveability faults, might be caused by this problem and go undiagnosed until the link lead (and the car)fails completely.

I had some ideas on early diagnosis, but I never followed up on them...there wasn't alot of evidence that this was a common problem. Anyone who is still reading this is welcomed to please contribute cases similar to XJ ate's post, and to offer suggestions on tests to identify this fault in its early stages. Otherwise, I might be the next guy waiting for a tow truck.

http://360.yahoo.com/my_profile-wuVb....inZYMs8-?cq=1

 

Hey Andy, YOU ROCK!!
Without your help I'd be lost and know I feel like this is not too bad.
It will probably be a few days before I look into getting this done, But I'll let ya know and try to get some photos to help others.

 

Jim, it's all good. That would be great to see some pictures to compare.

While the subject is still current, two questions if I may:

Have you seen a check engine warning at any point in the month you have owned the car?
Did the engine ever throw a big stumble while driving, or feel like it was down on power under load?

 

I have not had either light or stumble. Its been great up to this point except for the one 15min episode of cranking with no start, but then it worked just and for a few days or so.

Looks like a pump is hard to find in these parts, autozone says they have one in stock, but I usually stay clear of that place(too many customer problems I've had to listen to)

What the price form the dealer on pump and link lead I may go that route and have someone ship them to me, or maybe the Zone will get there chance to **** me off.

 

OOps I forgot nobody else in town(napa, kragen or pep) can get this thing.
Zones price is $101.99 for an airtex #e2471 if I remember correctly. Anyone know this brands quality?

 

I finally decided to tear into the fuel tank and remove the pump. The link lead plug wires look a little brown, but not burned at all - I'll post photos a bit later.

 

did you have fun disconnecting the lines over the diff in the bottom of the tank? Its the hardest at times of the whole job, especially is the check valve doesnt close and it starts drainin the tank of gas on you. I usually quote the pump, sock filter, link lead, and evap loss cap( white plastic cap on top of tank), this sometimes melts in the terminal sockets too. If not, I dont replace it and becomes cheaper for the customer, but at least we're not calling them back for more money and alot less in the end. You can always get parts from Ken at motorcars ltd. Jag tech, nice write up, I get to impatient to wite that much anymore since it seems as soon as I do I get the imfamous ERROR message and just lost a whole instruction manual type writeup. As fa as warly checkout, yes while its doing it if you depress the shrader valve and have no squirt of gas, you not getting fuel, mostly pumps. some link leads, but if I find bad link lead, youre getting a pump too since it would not be wise to spend money on labor and not replace a cheap pump when youre in there, especially when what would you response be when the pump goes out later and you have to explain to the customer why you didnt just install a new pump too since they go out more often than anything else fuel related

 

BRUTAL,

Thanks for the thumbs up, I know what you mean about writing long posts and watching them disappear into the ether.

Good to know about the terminals in the top flange, I hadn't seen or read about that on XJ8. It's pretty common on XJ40/ late XJS, and they had all the same failures. This is another case where a relatively common fault was tinkered with by subtle changes to the components, but no bulletproof fix was developed.

Even on my own car, I wouldn't want to risk doing that job twice...especially after getting stuck on the side of the road. Your plan is for sure the only way to go on customer pay cars, there's no doing that the second time when they are pissed and I'm working for free.

Did you have a read through the Actively seeking Suspension solutions thread? Just curious if you have any thoughts to contribute.

 

actually I was jut talking to a customer today about your thread on air suspension....especially since I put a air pump in his car a couple months ago. We talked about common failures on 04^XJ's air pump is the first to come to mind. I dont know that Jag will ever come out with a big fix for this, I think will probobly come from people like you and forums like this.....Jaguar will probobly redesign either system or pump to address this issue in the upcoming release( I hope)

 

Brutal I was able to remove the pump with out removing the tank completely. I undid all the lines and connections on top the tank and removed the filler neck from the boot it fits into and was able to wiggle it around enough to get it to tip forward to remove everything.
I removed the overflow tube completely so I did not damage it and finessed the main line on the driver side back behind the tank before attempting to move it. It was a B!t@h but i got it.
Thanks for the tips also, without those hour long toturials alot of us would be lost.

 

Okay here are the photos I took to maybe help anyone else that gets stuck doing this job themselves.

1st undo all hoses and connections on the top of the tank and remove the large locking ring. I used a flat head and a hammer to gently twist off the lock ring (not pictured, sorry)

http://i593.photobucket.com/albums/t...p/100_4105.jpg
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this pic kinda shows how far I moved and tilted the tank, also shows the unremovable wires that go through the fuel pipes connected to the tank so you can not remove the tank.

http://i593.photobucket.com/albums/t...p/100_4103.jpg
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In this pic I have undone the hoses and plugs and removed the housing from the tank.

http://i593.photobucket.com/albums/t...p/100_4102.jpg
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This is what the inside of the housing looks like, the pump is not in that blue part, so dont bother opening it because you WILL break it.

http://i593.photobucket.com/albums/t...p/100_4106.jpg
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I had to open it just to see and this is what is in there, so now you dont have to open yours and break it. Your welcome.

http://i593.photobucket.com/albums/t...p/100_4104.jpg
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The fuel pump will still be in the bottom of the tank, here it is. You can see the brownish rectangle below it, thats the strainer which you will need to replace along with the pump regaurdless of how clean it looks because it is the only way to get a warranty with your new pump.

http://i593.photobucket.com/albums/t...p/100_4100.jpg
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The pump is held in with just one little bolt, you can see it here to the left. I'm sure sure what size it is in metric but I used a 9/32 and it worked great. Remove that lil guy and the fuel line connected to the top of the pump (also see in this pic) and the pump pulls right out.

http://i593.photobucket.com/albums/t...p/100_4108.jpg
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Here is the picture of the "link lead" that I could only find from the Jag dealer. If it looks burnt, replace it. What happens is as your pump fails it demands more amps or voltage (I'm not a tech so I'm not sure which one causes the failure) and that extra power is too much for the link lead to handle and it will sometimes (pretty often) burn the wires and kill your connection. I believe mine looks okay, but I am going to test it before I seal it all back up.

http://i593.photobucket.com/albums/t...p/100_4101.jpg
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And after all is done you have your pump sitting on the ground in your driveway (this is a good time to show your nieghbors and let them know why you've spent the last two hours crammed into your own trunk).
Here you have the pump (the goldish colored unit) along with the link lead still attached to the top and the strainer attached at the bottom. The silver bracket will come off easliy by pulling the bottom part first and then sliding the top of the bracket off over the top of the pump. There are also a couple bushing on boths sides to keep everything inplace and tight, they are very self explanitary.

http://i593.photobucket.com/albums/t...p/100_4109.jpg
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I hope this helps someone, I know I could have used a few pics to help me through it.
Thank you Jagtech for all your help and to the other techs here that make life for the rest of us a lil easier.

 

The results are in...
My "link lead" is good, the pump is bad.

I tested the lead by inserting jumpers from a battery to the white lead connection and then used my testor to test voltage to the black connector that goes to the pump and I had full power.
I then connected the black plug to the fuel pump and got nothing, so I used my powered jump cables directly to the pumps connection and again got nothing. I rechecked that I had power to the black connection and I did...so its just the pump and I can keep the extra $120 for the lead in my pocket.

Quick question for the techs (or anyone who knows what they are doing) I didn't need any other type of ground to test the pump, correct, just the positive and negitive connections on the pump?
Thanks

 

Well I got it all back together and she is purring like a cat again. I took a few pics of the new pump and stainer that I'll post up tomorrow.
It all went back together real easy.
Thank You very much JagtechOhio and the others that put in some tips for me. It is very appreciated.

 

Tip o' the cap to you for a job well done...and not too painful in the long run.

If anyone is interested, the link below takes you to a photo I took of a cooked link lead.

http://www.flickr.com/photos/1107665...7604283198013/

If you click on 'all sizes' at the left above the photo, the enlargement shows a clear view of the connector.