XJ6 & XJ12 Series I, II & III 1968-1992

Fuel pump

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Old 07-29-2015, 01:36 PM
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Default Fuel pump

I think Doug told me a few days ago that I could prime the pump by putting it in gear and turning the key on. That's not working. I checked grounds and such, everything seams tight and not hacked at all. Any suggestions? it is still stalling at stops and I'm thinking there might be a relation to this.
 
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Old 07-29-2015, 02:34 PM
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Originally Posted by amaezing
I think Doug told me a few days ago that I could prime the pump by putting it in gear and turning the key on.

Not turning the key 'on' but, rather, turning the key to 'start'. Try it again !

Cheers
DD
 
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Old 07-29-2015, 03:10 PM
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Originally Posted by Doug
Not turning the key 'on' but, rather, turning the key to 'start'. Try it again !

Cheers
DD
Yea. Thanks. I was doing it wrong. It does work correctly. so that doesn't help my problem. Starts great in the morning when it's cold as it did the other day when I tried this the wrong way. after it gets warm it starts dying when I stop completely. a rolling stop no problem. a complete stop it dies. checked wiring grounds and everything looks good and feels tight. I have to go get the batttery checked still. I guess I'll go do that right now. talk soon.
 
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Old 07-29-2015, 03:52 PM
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Well it tested good, full charge, 1000 cranking amps, 1000 CA battery.
Any ideas to the stalling out issue and then hard starting?
 
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Old 07-29-2015, 08:31 PM
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all right tomorrow Im breaking out the ohm meter and test for resistance at all the grounds and go get me a timing light(I really miss my shop). Lets see if I can't find this freakin problem. I've had it! time to break out the gloves and go rounds.
 
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Old 07-30-2015, 04:05 AM
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Just trying to clarify, is it that when it is at operating temperature, it just won't idle, or is it more like the quicker stopping is making it stall?? Does it keep running if you keep your foot on the gas as well as the brake to keep some revs up? If it won't idle at all, it could be many things (fuel mix, "choke" staying on when it warmed up, too much/little air etc etc). If it is more the motion of stopping causing it to stall, it is something more physical, e.g loose wire/ground.
I remember an old 70's toyota I had that used to stall at stops unless it was put into neutral and some throttle applied. turned out that it was just a simple fuse marked 'engine'. replaced said fuse and she ran like a dream again.
I know that this is not of any help, I am just trying to narrow things down a bit.
 
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Old 07-30-2015, 04:50 AM
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I have been looking in my service handbook that came with my Jag, and looking at the fuses listed, I would be tempted to replace and test number 11 on both sides under the dash. they cover a large amount of things. Now, Lucas, Lord of Darkness and Alcoholism, in all his wisdom, has made Jags do weird things when fuses blow/fail, and not always what you would expect them to do. Try blowing the antenna fuse, and see what happens to the door lights for example.....
I don't know what the logic unit is or what it does, but its fuse is number 2 on left hand side under dash. Could be low coolant sensor fuse, number 4. for the way these things work, it could be the heated rear screen fuse.

It is probably nothing to do with fuses, just me rambling. I would suggest changing any of the original fuses though, just to be sure. Very little cost, and easy to do.

Another thought.... does yours have the emissions crap on it? Over here in New Zealand we don't need it so I wouldn't have the foggiest if that could be causing any of your problems. I don't know how it works at all.

I wish you good luck, and hope you solve the issue with relative ease
 

Last edited by Richard_gib; 07-30-2015 at 04:55 AM. Reason: bad spelling.
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Old 07-30-2015, 06:19 AM
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Richard_gib;1276908]Just trying to clarify, is it that when it is at operating temperature, it just won't idle,
It idles fine.

or is it more like the quicker stopping is making it stall??
Correct

Does it keep running if you keep your foot on the gas as well as the brake to keep some revs up?
yes, two footed stopping helps

If it won't idle at all, it could be many things (fuel mix, "choke" staying on when it warmed up, too much/little air etc
not sure this is the deal

If it is more the motion of stopping causing it to stall, it is something more physical, e.g loose wire/ground.
this is my thought "now"

I am going to go through the wires better today. And every idea helps me to narrow it down and see if I've descibed it correctly.
 

Last edited by amaezing; 07-30-2015 at 06:24 AM.
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Old 07-30-2015, 06:28 AM
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Originally Posted by Richard_gib
I have been looking in my service handbook that came with my Jag, and looking at the fuses listed, I would be tempted to replace and test number 11 on both sides under the dash. they cover a large amount of things. Now, Lucas, Lord of Darkness and Alcoholism, in all his wisdom, has made Jags do weird things when fuses blow/fail, and not always what you would expect them to do. Try blowing the antenna fuse, and see what happens to the door lights for example.....
I don't know what the logic unit is or what it does, but its fuse is number 2 on left hand side under dash. Could be low coolant sensor fuse, number 4. for the way these things work, it could be the heated rear screen fuse.

It is probably nothing to do with fuses, just me rambling. I would suggest changing any of the original fuses though, just to be sure. Very little cost, and easy to do.

Another thought.... does yours have the emissions crap on it? Over here in New Zealand we don't need it so I wouldn't have the foggiest if that could be causing any of your problems. I don't know how it works at all.

I wish you good luck, and hope you solve the issue with relative ease
Easy enough. I'll do it. that makes sense.
btw. I do have emmisions crap, it does have a leak at the cat also but i don't think it would cause anything like this. maybe it does but what a bit@# to fix.
 
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Old 07-30-2015, 06:46 AM
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Originally Posted by Richard_gib
Over here in New Zealand we don't need it so I wouldn't have the foggiest if that could be causing any of your problems.
Haha, haven't heard anyone say foggiest since I left NZ back in 1989.
 
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Old 07-30-2015, 07:14 AM
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I have it all disconnected anyway. Ill hook it up when I go get emmision test done and then disconnect it again afterward. It is a power loss and the stupid pumps go out all the time and they are expensive to replace.
 
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Old 07-30-2015, 08:25 AM
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Originally Posted by amaezing
after it gets warm it starts dying when I stop completely. a rolling stop no problem. a complete stop it dies.

Any sense that it might be flooding out? Any black smoke? Try unplugging the coolant temp sensor and jumping the 2 terminals inside the plug. Use a paper clip. Any difference?

Next, for the heck of it, run a jumper from the battery "+" post to the coil "+" post. and drive. Any difference?

Have we talked about idle speed, cleaning the throttle bore, the .002" throttle gap? How about the ducting from the air flow meter to the throttle body? No leaks or splits?

Cheers
DD
 
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Old 07-30-2015, 08:28 AM
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Originally Posted by amaezing
Easy enough. I'll do it. that makes sense.
btw. I do have emmisions crap, it does have a leak at the cat also but i don't think it would cause anything like this. maybe it does but what a bit@# to fix.

I presume you removed the air injection? Lots of people do that, shouldn't be a problem.

I don't think a leak at the cat would cause any stalling. There's no way the fuel injection system or ignition system would know or care if there was a leak.

Cheers
DD
 
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Old 07-30-2015, 08:59 AM
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Default Ignition switch

My SII used to "stop/turn off" when making right turns.. due to the keys weight on the key ring making the worn out switch "turn off". Common problem...
 
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Old 07-30-2015, 09:07 AM
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Originally Posted by Doug
Any sense that it might be flooding out? Any black smoke? Try unplugging the coolant temp sensor and jumping the 2 terminals inside the plug. Use a paper clip. Any difference?

Next, for the heck of it, run a jumper from the battery "+" post to the coil "+" post. and drive. Any difference?

Have we talked about idle speed, cleaning the throttle bore, the .002" throttle gap? How about the ducting from the air flow meter to the throttle body? No leaks or splits?

Cheers
DD
Not flooding.
I'll try the paper clip trick
I believe I already tried the coil jump but I'll try it again.
I tried to find out how to turn idle up on here, but never got an answer. throttle bore is way clean and gap is correct(double checked Twice), I'll check the duct once more(probably 3rd or 4th time)
 
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Old 07-30-2015, 09:09 AM
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Default Fuel pump

A few years ago I had a '98 XJ that had a similar issue. After playing around with an ohm meter and fuses I just had someone get in and try to crank it while I wiggled the wires. When I forced the pig tail into the pump contacts the car cranked right up. I took a closer look at the harness and noticed that when the previous pump had burned out it got hot and partially melted the plastic around the metal contact on the pig tail connecting to the pump. So to fix it I had our parts dept. order a used harness from Coventry and I just borrowed the pig tail from that one. That fixed the problem. Good luck!
Originally Posted by amaezing
I think Doug told me a few days ago that I could prime the pump by putting it in gear and turning the key on. That's not working. I checked grounds and such, everything seams tight and not hacked at all. Any suggestions? it is still stalling at stops and I'm thinking there might be a relation to this.
 
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Old 07-30-2015, 09:10 AM
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Originally Posted by Roger Mabry
My SII used to "stop/turn off" when making right turns.. due to the keys weight on the key ring making the worn out switch "turn off". Common problem...
Yea, this is common on alot of older cars. I only have the two keys and a ring for a very long time on all my cars because of this common problem. I'm guessing that a hot jump from battery to coil will narrow this problem down.
 
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Old 07-30-2015, 09:12 AM
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Originally Posted by JoeyC
A few years ago I had a '98 XJ that had a similar issue. After playing around with an ohm meter and fuses I just had someone get in and try to crank it while I wiggled the wires. When I forced the pig tail into the pump contacts the car cranked right up. I took a closer look at the harness and noticed that when the previous pump had burned out it got hot and partially melted the plastic around the metal contact on the pig tail connecting to the pump. So to fix it I had our parts dept. order a used harness from Coventry and I just borrowed the pig tail from that one. That fixed the problem. Good luck!
Thanks, Ill check it out.
 
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Old 07-30-2015, 09:14 AM
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Originally Posted by Doug
I presume you removed the air injection? Lots of people do that, shouldn't be a problem.

I don't think a leak at the cat would cause any stalling. There's no way the fuel injection system or ignition system would know or care if there was a leak.

Cheers
DD
Air injection? no I did not remove it. I simply took the belt off.
yea a leak in the cat is nothing more than a noise. hasn't even affected the sensor that I know of.
 
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Old 07-30-2015, 09:30 AM
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there is no "plug" on the pump. so that is not it. Thanks though.
I have an appointment on the other side of town in a few hours, so I'm going to do the paper clip trick then and see what happens. made a jumper for the coil jump to have on hand if the paper clip doesn't work.
changed every fuse with new ones, there were alot of original ones in it(most of them).
Im not relly convinced that it's out of time right yet, going to keep that in the back of my mind though. I really don't see the connection with this problem.
Checked all the grounds with the meter and felt to see if they were in the slightest bit loose. all were tight and tested good. I'm gonna get this freakin thing figured out today!!!!
THANK YOU ALL FOR YOUR SUGGESTIONS!!!
 


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