What EXACTLY does the 2003 Jaguar XK8 X100 Fuel Pump Control Module do?
#23
I think what folks are getting at replying to the thread is that new/used or otherwise - it may not be what's needed... I wouldnt spring for a replacement just yet unless you have NONE right now. If you have none, I would get a used part. They are pretty solid and not a component I have heard a lot about going bad.
If you don't mind,,, what exactly is the issue you have right now? Besides not having a fuel pump driver/regulator (if indeed you don't)...
If you don't mind,,, what exactly is the issue you have right now? Besides not having a fuel pump driver/regulator (if indeed you don't)...
#25
The car would not run at all without one of these, with a bad one, or - I dare say - with the WRONG one all together... A test is to bypass the fuel pump regulator/module (which I've done) and see what you get.
I also had the valve, the one built INTO the fuel pump assembly (the one super well photographed by a memeber in the post earlier in the thread) go bad. The valve turned out to be seeezed and by a super stroke of luck I ended up with a second one and had it on hand. I could NOT find the valve shopping the world wide web. Didn't even know how to ID it. Anyways,,, symptoms of the seeezed was higher than right pressures when driving and very high pressures at shut down 80-90lbs +... And upon installing the "new" one (I pinched and damaged the Oring (see photo earlier in thread) assembling the "new" valve in the assembly),,, which resulted in a long crank at start up, wouldn't hold pressure well while idling and pressures would drop to 20-30lbs when driving. Up hill, forget about it!!! Blah blah blah
Jus say'n,,,, I think you would do well by giving folks a play by play of what it is,,, OR ISN'T,,, you are experiencing right now.
I also had the valve, the one built INTO the fuel pump assembly (the one super well photographed by a memeber in the post earlier in the thread) go bad. The valve turned out to be seeezed and by a super stroke of luck I ended up with a second one and had it on hand. I could NOT find the valve shopping the world wide web. Didn't even know how to ID it. Anyways,,, symptoms of the seeezed was higher than right pressures when driving and very high pressures at shut down 80-90lbs +... And upon installing the "new" one (I pinched and damaged the Oring (see photo earlier in thread) assembling the "new" valve in the assembly),,, which resulted in a long crank at start up, wouldn't hold pressure well while idling and pressures would drop to 20-30lbs when driving. Up hill, forget about it!!! Blah blah blah
Jus say'n,,,, I think you would do well by giving folks a play by play of what it is,,, OR ISN'T,,, you are experiencing right now.
#26
Well, I bought this 2003 XK8 about 2 months ago and I drove it home. I have had trouble with it on and off with long start Cycles. Then it got to the point that it would not start at all .
I got with the previous owner and he said that he had a new fuel pump and pump drive module installed by a mechanic. I called the mechanic that did the work and they warranty their parts and labor for two years. I had the car towed to their shop and he apparently did some tests by jumping past the drive module he was able to start the car and drive it around, but when he shut the engine off it doesn't hold fuel pressure on the fuel rail. He wasn't able to find a new fuel pump drive module for my car, so he ordered one on eBay and put it in the other day. The car still doesn't start. He is wondering if he got a bad fuel pump drive module from eBay.
I am very frustrated at this point because it is a very nice car with very few miles on it, but if you can't drive it and enjoy it why even have it?
Smokey59
I got with the previous owner and he said that he had a new fuel pump and pump drive module installed by a mechanic. I called the mechanic that did the work and they warranty their parts and labor for two years. I had the car towed to their shop and he apparently did some tests by jumping past the drive module he was able to start the car and drive it around, but when he shut the engine off it doesn't hold fuel pressure on the fuel rail. He wasn't able to find a new fuel pump drive module for my car, so he ordered one on eBay and put it in the other day. The car still doesn't start. He is wondering if he got a bad fuel pump drive module from eBay.
I am very frustrated at this point because it is a very nice car with very few miles on it, but if you can't drive it and enjoy it why even have it?
Smokey59
Last edited by Smokey59; 03-14-2022 at 06:30 PM.
#27
Smokey'er than most others!
You continue to complain about your Car not running! Several of us have given you different scenarios to try but I'm concerned that you have not tried any of them...Apparently, you have not tried mine as you have not mentioned whether it worked or not.....I guess you think it's too simple! Hope you have a wonderful Day!
Billy Clyde
You continue to complain about your Car not running! Several of us have given you different scenarios to try but I'm concerned that you have not tried any of them...Apparently, you have not tried mine as you have not mentioned whether it worked or not.....I guess you think it's too simple! Hope you have a wonderful Day!
Billy Clyde
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kstevusa (03-15-2022)
#28
Well, I bought this 2003 XK8 about 2 months ago and I drove it home. I have had trouble with it on and off with long start Cycles. Then it got to the point that it would not start at all .
I got with the previous owner and he said that he had a new fuel pump and pump drive module installed by a mechanic. I called the mechanic that did the work and they warranty their parts and labor for two years. I had the car towed to their shop and he apparently did some tests by jumping past the drive module he was able to start the car and drive it around, but when he shut the engine off it doesn't hold fuel pressure on the fuel rail. He wasn't able to find a new fuel pump drive module for my car, so he ordered one on eBay and put it in the other day. The car still doesn't start. He is wondering if he got a bad fuel pump drive module from eBay.
I am very frustrated at this point because it is a very nice car with very few miles on it, but if you can't drive it and enjoy it why even have it?
Smokey59
I got with the previous owner and he said that he had a new fuel pump and pump drive module installed by a mechanic. I called the mechanic that did the work and they warranty their parts and labor for two years. I had the car towed to their shop and he apparently did some tests by jumping past the drive module he was able to start the car and drive it around, but when he shut the engine off it doesn't hold fuel pressure on the fuel rail. He wasn't able to find a new fuel pump drive module for my car, so he ordered one on eBay and put it in the other day. The car still doesn't start. He is wondering if he got a bad fuel pump drive module from eBay.
I am very frustrated at this point because it is a very nice car with very few miles on it, but if you can't drive it and enjoy it why even have it?
Smokey59
Dude. Get the 40-50 dollar fuel pump regulator module thing in the link above (if that's what you think you need to do) and plug it in. That part takes minutes and a few bucks. The testing procedure, because it's pulse width modulation (PWM) requires an osilliscope and some care. From memory, there are 6 wires in the connector/harness. One is main ground, two (thin white) are signals to and from the ECU, two are 12v (one the main 12v and the other the voltage to the pump) and the last, the control ground I believe which controls the "switching" turning the pump on and off in milliseconds... I would dig deeper but I'm not sure you would take the suggestions AND, it ain't easy.
Can't you take a DMM or a test light and see if you are getting power to the pump, to the module, do you have a wire diagram?
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kstevusa (03-15-2022)
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Paul1940 (11-30-2022)
#30
The thing is, the car is at an Auto Repair Shop. The mechanic suspected that the fuel pump drive module is bad in my car, so he purchased a used one (from eBay) to replace the one that's in the car now. I called him yesterday and ask him how it was going and he said that they received the used fuel pump drive module (from eBay) and installed it, but he thinks it may be bad as well.
The mechanic is also informing me that there are two gray wires in the trunk area near that fuel pump drive module that are not in use, and so he is curious if those belong to something related or not.
To your question about having a wiring diagram...... No I do not.
Smokey59
The mechanic is also informing me that there are two gray wires in the trunk area near that fuel pump drive module that are not in use, and so he is curious if those belong to something related or not.
To your question about having a wiring diagram...... No I do not.
Smokey59
Last edited by Smokey59; 03-15-2022 at 06:35 AM.
#31
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The thing is, the car is at an Auto Repair Shop. The mechanic suspected that the fuel pump drive module is bad in my car, so he purchased a used one (from eBay) to replace the one that's in the car now. I called him yesterday and ask him how it was going and he said that they received the used fuel pump drive module (from eBay) and installed it, but he thinks it may be bad as well.
It's available from member Gus' website:
http://www.jagrepair.com/images/Auto.../jagxk2003.pdf
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JimmyL (03-17-2022)
#32
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Dr. D (11-27-2022)
#34
Smokey59,
I've had this problem and even replaced the VDO Driver....but it still didn't work!!!! I visited with Charlie by email and as I told you earlier...I tightened all the contacts around the Gas Tank including the VDO Modul and dropped a drop of Solder on each connection.....Charlie said that vibration apparently loosened the connection over time......I've not had any problems in over a year with the same set-up that wouldn't run a year ago....As Charlie said, it would have to be the connections....
By doing this...I believe that nothing has been wrong with any of the (4) $650.00 to $700.00 Fuel Pumps that I bought over the years.....It is apparently the connections vibrating loose! It worked for me! Ask Charlie.............
I just went out to the Garage and She started right up!!! This works!
Billy Clyde @ Cinco Ranch
I've had this problem and even replaced the VDO Driver....but it still didn't work!!!! I visited with Charlie by email and as I told you earlier...I tightened all the contacts around the Gas Tank including the VDO Modul and dropped a drop of Solder on each connection.....Charlie said that vibration apparently loosened the connection over time......I've not had any problems in over a year with the same set-up that wouldn't run a year ago....As Charlie said, it would have to be the connections....
By doing this...I believe that nothing has been wrong with any of the (4) $650.00 to $700.00 Fuel Pumps that I bought over the years.....It is apparently the connections vibrating loose! It worked for me! Ask Charlie.............
I just went out to the Garage and She started right up!!! This works!
Billy Clyde @ Cinco Ranch
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Paul1940 (11-30-2022)
#38
#39
The manuals can be taken from the "JagRepair" web site. Wonderful resources there!
#40