Plug Fouling 96 D1. All plugs.
Baja
Joined: Mar 2010
Posts: 5,584
Likes: 7
From: Pittsburgh PA suburbs.
A fresh thought just occurred to me (been a long time since that last happened).
After reading some of this and some other postings where sensor values were way off or an erratic sensor reading was causing a problem, wouldn't it be possible to disconnect the sensor and temporarily jumper in a variable resistor as a substitute so that the input could be varied to see what effect that has on the specific function that is malfunctioning?
I realize this may sound pretty farout to some of you guys, but it seems like a possible worthwhile troubleshooting method when faced with a difficult to analyze problem and a cheaper and possibly easier method than changing out parts hoping that that resolves the problem.
I am throwing this out as food for thought, as I am sure that a lot of you still use those thought processes more frequently and to a higher degree than I now am required to do.
It's been several years since I was involved in the analysis and resolution of significant technical issues, but occasionally a thought does manage to surface once again.
I really hope you get to the bottom of this. I like learning what specifics defects/faults are determined to be the root cause of an equipment problem.
The days of troubleshooting on the flight deck as the ship tosses in the rising and fallling tides are a distant memory , but every once in a while .................Just an old sailor reminiscing.................
After reading some of this and some other postings where sensor values were way off or an erratic sensor reading was causing a problem, wouldn't it be possible to disconnect the sensor and temporarily jumper in a variable resistor as a substitute so that the input could be varied to see what effect that has on the specific function that is malfunctioning?
I realize this may sound pretty farout to some of you guys, but it seems like a possible worthwhile troubleshooting method when faced with a difficult to analyze problem and a cheaper and possibly easier method than changing out parts hoping that that resolves the problem.
I am throwing this out as food for thought, as I am sure that a lot of you still use those thought processes more frequently and to a higher degree than I now am required to do.
It's been several years since I was involved in the analysis and resolution of significant technical issues, but occasionally a thought does manage to surface once again.
I really hope you get to the bottom of this. I like learning what specifics defects/faults are determined to be the root cause of an equipment problem.
The days of troubleshooting on the flight deck as the ship tosses in the rising and fallling tides are a distant memory , but every once in a while .................Just an old sailor reminiscing.................
Last edited by Danny Lee 97 Disco; Jan 13, 2011 at 01:13 PM.
Baja
Joined: Mar 2010
Posts: 5,584
Likes: 7
From: Pittsburgh PA suburbs.
You may have an intermittent connection in the wiring associated with the coolant temp sensor. The sensor itself may not be the physical problem, but it sounds like the signal from the temp sensor to the ecu or the associated ground is a very strong candidate for your true root cause. I spent 20 years involved in the manufacture/maintenance /testing/failure analysis of military aircraft and defense missiles, the last ten devoted entirely to root cause analysis and corrective action segment of the Tomahawk Cruise Missile. The majority of the program's test failures were associated with damaged or degraded wiring.
Check all your associated grounds as a favor to your sanity.
Check all your associated grounds as a favor to your sanity.
Baja
Joined: Mar 2010
Posts: 5,584
Likes: 7
From: Pittsburgh PA suburbs.
One other question regarding the fuel leak, have you taken the cover off the fuel pump assembly to see what conditions you have at the top of the fuel pump?
I am talking about the black panel under the rear deck carpet/pad. The fact that you lost a half tank overnight does indicate a significant leak associated with the fuel supply/return lines.
With the key on the fuel pump only runs a few seconds to prime the system, if you don't start the vehicle, the fuel pump goes back off after 5 seconds or so. Having 0 pressure right after cutting the engine off is not normal either. The system should maintain pressure for a significant time frame if it is not leaking.
My fuel lines were so corroded that when I lifted the lines out of the mountings clamps while troubleshooting an intermittent starter problem that I developed several pinhole leaks. The lines had corroded to the clamps all along the rounting from the tank to the engine bay and back as well as the filter corroding to it's clamp. I lost a half tank overnight sitting in my driveway. When I took a close look at the lines, they were so bad it was horrndous. I bought a 25 foot coil of 5/16 fuel line and hand formed and rerouted both lines all the way from tank to engine bay.
If you have not yet looked at the top of your fuel pump, you need to pull the black plate from the rear deck and see what you got bubba. Take a look at my photo album and you will see some pics of the condition of the fuel lines that were in mine when I first bought it.
And don't buy any more Land Rovers from the Walmart Parking lot. Some poor homeless guy could have enjoyed living in it instead of a box or under a tarp. Talk about a Blue Light Special. How did you stumble upon such a deal?
I am talking about the black panel under the rear deck carpet/pad. The fact that you lost a half tank overnight does indicate a significant leak associated with the fuel supply/return lines.
With the key on the fuel pump only runs a few seconds to prime the system, if you don't start the vehicle, the fuel pump goes back off after 5 seconds or so. Having 0 pressure right after cutting the engine off is not normal either. The system should maintain pressure for a significant time frame if it is not leaking.
My fuel lines were so corroded that when I lifted the lines out of the mountings clamps while troubleshooting an intermittent starter problem that I developed several pinhole leaks. The lines had corroded to the clamps all along the rounting from the tank to the engine bay and back as well as the filter corroding to it's clamp. I lost a half tank overnight sitting in my driveway. When I took a close look at the lines, they were so bad it was horrndous. I bought a 25 foot coil of 5/16 fuel line and hand formed and rerouted both lines all the way from tank to engine bay.
If you have not yet looked at the top of your fuel pump, you need to pull the black plate from the rear deck and see what you got bubba. Take a look at my photo album and you will see some pics of the condition of the fuel lines that were in mine when I first bought it.
And don't buy any more Land Rovers from the Walmart Parking lot. Some poor homeless guy could have enjoyed living in it instead of a box or under a tarp. Talk about a Blue Light Special. How did you stumble upon such a deal?
Last edited by Danny Lee 97 Disco; Jan 13, 2011 at 01:15 PM.
Thread Starter
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Winching
Joined: Jul 2010
Posts: 683
Likes: 3
One other question regarding the fuel leak, have you taken the cover off the fuel pump assembly to see what conditions you have at the top of the fuel pump?
I am talking about the black panel under the rear deck carpet/pad. The fact that you lost a half tank overnight does indicate a significant leak associated with the uel supply/return lines.
With the key n the fuel pump only runs a few seconds to prime the system, if you don't start the vehicle, the fuel pump goes back off after 5 seconds or so. Having 0 pressureright after cutting the engine ff isnot normal either. The system should maintain pressure for a significant time frame if it is not leaking.
My fuel lines were so corroded that when I lifted the lines out of the mountings clamps while troubleshooting a n intermittent starter problem that I developed several pinhole leaks. The lines had corroded to the clamps all along the rounting from the tank to the engine bay and back as well as the filter corroding to it's clamp. I lost a halftank overnight sitting in my driveway. When I took a close look at the lines, they were so bad it was horrndous. I bought a 25 foot coil of 5/16 fuel line and hand formed and rerouted both lines all the way from tank to engine bay.
If you have not yet looked at the top of your fuel pump, you need to pull the black plate from the rear deck and see what you got bubba. Take a look at my photo album and you will see some pics of the condition of the fuel lines that were in mine when I first bought it.
And don't buy any more Land Rovers from the Walmart Parking lot. Some poor homeless guy could have enjoyed living in it instead of a box or under a tarp. Talk about a Blue Light Special. How did you stumble upon such a deal?
I am talking about the black panel under the rear deck carpet/pad. The fact that you lost a half tank overnight does indicate a significant leak associated with the uel supply/return lines.
With the key n the fuel pump only runs a few seconds to prime the system, if you don't start the vehicle, the fuel pump goes back off after 5 seconds or so. Having 0 pressureright after cutting the engine ff isnot normal either. The system should maintain pressure for a significant time frame if it is not leaking.
My fuel lines were so corroded that when I lifted the lines out of the mountings clamps while troubleshooting a n intermittent starter problem that I developed several pinhole leaks. The lines had corroded to the clamps all along the rounting from the tank to the engine bay and back as well as the filter corroding to it's clamp. I lost a halftank overnight sitting in my driveway. When I took a close look at the lines, they were so bad it was horrndous. I bought a 25 foot coil of 5/16 fuel line and hand formed and rerouted both lines all the way from tank to engine bay.
If you have not yet looked at the top of your fuel pump, you need to pull the black plate from the rear deck and see what you got bubba. Take a look at my photo album and you will see some pics of the condition of the fuel lines that were in mine when I first bought it.
And don't buy any more Land Rovers from the Walmart Parking lot. Some poor homeless guy could have enjoyed living in it instead of a box or under a tarp. Talk about a Blue Light Special. How did you stumble upon such a deal?
Baja
Joined: Mar 2010
Posts: 5,584
Likes: 7
From: Pittsburgh PA suburbs.
Please enlighten me, what instantly vents the pressure to 0 other than a significant leak?
There is nothing in the system that I am aware of that is designed to return the pressure to 0 immediately after shutdown.
And why does the RAVE caution you to vent the fuel pressure off prior to changing the fuel filter?
Baja
Joined: Mar 2010
Posts: 5,584
Likes: 7
From: Pittsburgh PA suburbs.
I don't think so. When you switch the key off, you are killing the power to the engine and the fuel pump at the same time, it is not like the engine continues to run after the fuel pump is shut off.
Pro Wrench
Joined: Apr 2010
Posts: 1,482
Likes: 8
From: Gramercy, La
Electronics go off before engine has completely stopped, but fuel injectors are electronic. I dont care. Mine doesn't leak and my fuel pressure is 0-10 after shutoff