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98 pace arrow /4 fuel pumps later losing fuel pressure after sometimes 50 miles then other times 300 miles is not vapor locking because just as soon as you pull off and shut down engine it will start back up wait an hour it will go maybe another 50 to whenever it decides to start bogging down again. have changed fuel filters hoping for bad fuel not helped except for cool down time
98 pace arrow /4 fuel pumps later losing fuel pressure after sometimes 50 miles then other times 300 miles is not vapor locking because just as soon as you pull off and shut down engine it will start back up wait an hour it will go maybe another 50 to whenever it decides to start bogging down again. have changed fuel filters hoping for bad fuel not helped except for cool down time
Bearing in mind that 90% of fuel problems are ignition problems, the first thing is to determine if you do, indeed have a fuel volume/pressure problem. on one of the steel tubes connecting the injectors on either bank of cylinders is a Schrader valve---looks just like a tire valve and works the same way. It's for connecting a test gauge to check for pressure and a hose can also be connected there to check volume. Pressure can be checked after engine has just been shut down, you have to by-pass the fuel pump relay for valume test. I'm not sure about your chassis, for years Ford used two pumps, one low pressure pump mounted in-tank to transfer fuel to a frame mounted high pressure pump. You might want to check that out to see if you've got this system.What with the large volume of fuel returned to the tank by the fuel pressure regulator, vapor lock is very seldom encountered any more. Ford did have trouble with their regulators, but that was a ruptured diaphragm which allowed copious amounts of gasoline to be sucked into the intake manifold via the vacuum hose attached to the regulator.
98 pace arrow /4 fuel pumps later losing fuel pressure after sometimes 50 miles then other times 300 miles is not vapor locking because just as soon as you pull off and shut down engine it will start back up wait an hour it will go maybe another 50 to whenever it decides to start bogging down again. have changed fuel filters hoping for bad fuel not helped except for cool down time
Bearing in mind that 90% of fuel problems are ignition problems, the first thing is to determine if you do, indeed have a fuel volume/pressure problem. on one of the steel tubes connecting the injectors on either bank of cylinders is a Schrader valve---looks just like a tire valve and works the same way. It's for connecting a test gauge to check for pressure and a hose can also be connected there to check volume. Pressure can be checked after engine has just been shut down, you have to by-pass the fuel pump relay for valume test. I'm not sure about your chassis, for years Ford used two pumps, one low pressure pump mounted in-tank to transfer fuel to a frame mounted high pressure pump. You might want to check that out to see if you've got this system.What with the large volume of fuel returned to the tank by the fuel pressure regulator, vapor lock is very seldom encountered any more. Ford did have trouble with their regulators, but that was a ruptured diaphragm which allowed copious amounts of gasoline to be sucked into the intake manifold via the vacuum hose attached to the regulator.
I did attach a fuel pressure gage to the manifold thats how i know the pressure is dropping its also not dropping off all at once most of the time its when you put a small load such as going over an overpass while traveling on a flat highway if I contine on then the pressure and speed drops off slowly I don't think that the electrical supply to the fuel pump is going and returning I didn't find a booster pump like ford is putting on thier new cars now
98 pace arrow /4 fuel pumps later losing fuel pressure after sometimes 50 miles then other times 300 miles is not vapor locking because just as soon as you pull off and shut down engine it will start back up wait an hour it will go maybe another 50 to whenever it decides to start bogging down again. have changed fuel filters hoping for bad fuel not helped except for cool down time
Bearing in mind that 90% of fuel problems are ignition problems, the first thing is to determine if you do, indeed have a fuel volume/pressure problem. on one of the steel tubes connecting the injectors on either bank of cylinders is a Schrader valve---looks just like a tire valve and works the same way. It's for connecting a test gauge to check for pressure and a hose can also be connected there to check volume. Pressure can be checked after engine has just been shut down, you have to by-pass the fuel pump relay for valume test. I'm not sure about your chassis, for years Ford used two pumps, one low pressure pump mounted in-tank to transfer fuel to a frame mounted high pressure pump. You might want to check that out to see if you've got this system.What with the large volume of fuel returned to the tank by the fuel pressure regulator, vapor lock is very seldom encountered any more. Ford did have trouble with their regulators, but that was a ruptured diaphragm which allowed copious amounts of gasoline to be sucked into the intake manifold via the vacuum hose attached to the regulator.
I did attach a fuel pressure gage to the manifold thats how i know the pressure is dropping its also not dropping off all at once most of the time its when you put a small load such as going over an overpass while traveling on a flat highway if I contine on then the pressure and speed drops off slowly I don't think that the electrical supply to the fuel pump is going and returning I didn't find a booster pump like ford is putting on thier new cars now.
OK, it's got only the single high pressure pump in the tank. Since you have a pressure gauge and know how to use it, hook it up to the test valve, start engine and run for 5 minutes at idle, record pressure. Remove vacuum hose from top of fuel pressure regulator( it's right on the fuel rail,(tubing),pressure should jump to 40-45Lb PSI if pump pressure and regulator are good. Come back with what you find.
98 pace arrow /4 fuel pumps later losing fuel pressure after sometimes 50 miles then other times 300 miles is not vapor locking because just as soon as you pull off and shut down engine it will start back up wait an hour it will go maybe another 50 to whenever it decides to start bogging down again. have changed fuel filters hoping for bad fuel not helped except for cool down time
Bearing in mind that 90% of fuel problems are ignition problems, the first thing is to determine if you do, indeed have a fuel volume/pressure problem. on one of the steel tubes connecting the injectors on either bank of cylinders is a Schrader valve---looks just like a tire valve and works the same way. It's for connecting a test gauge to check for pressure and a hose can also be connected there to check volume. Pressure can be checked after engine has just been shut down, you have to by-pass the fuel pump relay for valume test. I'm not sure about your chassis, for years Ford used two pumps, one low pressure pump mounted in-tank to transfer fuel to a frame mounted high pressure pump. You might want to check that out to see if you've got this system.What with the large volume of fuel returned to the tank by the fuel pressure regulator, vapor lock is very seldom encountered any more. Ford did have trouble with their regulators, but that was a ruptured diaphragm which allowed copious amounts of gasoline to be sucked into the intake manifold via the vacuum hose attached to the regulator.
I did attach a fuel pressure gage to the manifold thats how i know the pressure is dropping its also not dropping off all at once most of the time its when you put a small load such as going over an overpass while traveling on a flat highway if I contine on then the pressure and speed drops off slowly I don't think that the electrical supply to the fuel pump is going and returning I didn't find a booster pump like ford is putting on thier new cars now.
OK, it's got only the single high pressure pump in the tank. Since you have a pressure gauge and know how to use it, hook it up to the test valve, start engine and run for 5 minutes at idle, record pressure. Remove vacuum hose from top of fuel pressure regulator( it's right on the fuel rail,(tubing),pressure should jump to 40-45Lb PSI if pump pressure and regulator are good. Come back with what you find.
kent ,at idle the pressure reads about 28 to 30 .when I first turn on the key it jumps to about 38 then the relay clicks it drops to 30 when Istart the engine it drops to @26 then when i do like you said it goes to around 45 I have run it down the road while monoriting the pressure 20 miles later the pressure drops to 24 to 25 maybe a bad regulator will let you know as soon as get it replaced tommorrow thanks for the help so far .I was going to restrict bypass but I think I might cause other problems so I'm replacing the reg first.
98 pace arrow /4 fuel pumps later losing fuel pressure after sometimes 50 miles then other times 300 miles is not vapor locking because just as soon as you pull off and shut down engine it will start back up wait an hour it will go maybe another 50 to whenever it decides to start bogging down again. have changed fuel filters hoping for bad fuel not helped except for cool down time
Bearing in mind that 90% of fuel problems are ignition problems, the first thing is to determine if you do, indeed have a fuel volume/pressure problem. on one of the steel tubes connecting the injectors on either bank of cylinders is a Schrader valve---looks just like a tire valve and works the same way. It's for connecting a test gauge to check for pressure and a hose can also be connected there to check volume. Pressure can be checked after engine has just been shut down, you have to by-pass the fuel pump relay for valume test. I'm not sure about your chassis, for years Ford used two pumps, one low pressure pump mounted in-tank to transfer fuel to a frame mounted high pressure pump. You might want to check that out to see if you've got this system.What with the large volume of fuel returned to the tank by the fuel pressure regulator, vapor lock is very seldom encountered any more. Ford did have trouble with their regulators, but that was a ruptured diaphragm which allowed copious amounts of gasoline to be sucked into the intake manifold via the vacuum hose attached to the regulator.
I did attach a fuel pressure gage to the manifold thats how i know the pressure is dropping its also not dropping off all at once most of the time its when you put a small load such as going over an overpass while traveling on a flat highway if I contine on then the pressure and speed drops off slowly I don't think that the electrical supply to the fuel pump is going and returning I didn't find a booster pump like ford is putting on thier new cars now.
OK, it's got only the single high pressure pump in the tank. Since you have a pressure gauge and know how to use it, hook it up to the test valve, start engine and run for 5 minutes at idle, record pressure. Remove vacuum hose from top of fuel pressure regulator( it's right on the fuel rail,(tubing),pressure should jump to 40-45Lb PSI if pump pressure and regulator are good. Come back with what you find.
kent ,at idle the pressure reads about 28 to 30 .when I first turn on the key it jumps to about 38 then the relay clicks it drops to 30 when Istart the engine it drops to @26 then when i do like you said it goes to around 45 I have run it down the road while monoriting the pressure 20 miles later the pressure drops to 24 to 25 maybe a bad regulator will let you know as soon as get it replaced tommorrow thanks for the help so far .I was going to restrict bypass but I think I might cause other problems so I'm replacing the reg first.
98 pace arrow /4 fuel pumps later losing fuel pressure after sometimes 50 miles then other times 300 miles is not vapor locking because just as soon as you pull off and shut down engine it will start back up wait an hour it will go maybe another 50 to whenever it decides to start bogging down again. have changed fuel filters hoping for bad fuel not helped except for cool down time
Bearing in mind that 90% of fuel problems are ignition problems, the first thing is to determine if you do, indeed have a fuel volume/pressure problem. on one of the steel tubes connecting the injectors on either bank of cylinders is a Schrader valve---looks just like a tire valve and works the same way. It's for connecting a test gauge to check for pressure and a hose can also be connected there to check volume. Pressure can be checked after engine has just been shut down, you have to by-pass the fuel pump relay for valume test. I'm not sure about your chassis, for years Ford used two pumps, one low pressure pump mounted in-tank to transfer fuel to a frame mounted high pressure pump. You might want to check that out to see if you've got this system.What with the large volume of fuel returned to the tank by the fuel pressure regulator, vapor lock is very seldom encountered any more. Ford did have trouble with their regulators, but that was a ruptured diaphragm which allowed copious amounts of gasoline to be sucked into the intake manifold via the vacuum hose attached to the regulator.
I did attach a fuel pressure gage to the manifold thats how i know the pressure is dropping its also not dropping off all at once most of the time its when you put a small load such as going over an overpass while traveling on a flat highway if I contine on then the pressure and speed drops off slowly I don't think that the electrical supply to the fuel pump is going and returning I didn't find a booster pump like ford is putting on thier new cars now.
OK, it's got only the single high pressure pump in the tank. Since you have a pressure gauge and know how to use it, hook it up to the test valve, start engine and run for 5 minutes at idle, record pressure. Remove vacuum hose from top of fuel pressure regulator( it's right on the fuel rail,(tubing),pressure should jump to 40-45Lb PSI if pump pressure and regulator are good. Come back with what you find.
kent ,at idle the pressure reads about 28 to 30 .when I first turn on the key it jumps to about 38 then the relay clicks it drops to 30 when Istart the engine it drops to @26 then when i do like you said it goes to around 45 I have run it down the road while monoriting the pressure 20 miles later the pressure drops to 24 to 25 maybe a bad regulator will let you know as soon as get it replaced tommorrow thanks for the help so far .I was going to restrict bypass but I think I might cause other problems so I'm replacing the reg first.
as usual a dealer stock item ordered maybe monday will let you know
98 pace arrow /4 fuel pumps later losing fuel pressure after sometimes 50 miles then other times 300 miles is not vapor locking because just as soon as you pull off and shut down engine it will start back up wait an hour it will go maybe another 50 to whenever it decides to start bogging down again. have changed fuel filters hoping for bad fuel not helped except for cool down time
Bearing in mind that 90% of fuel problems are ignition problems, the first thing is to determine if you do, indeed have a fuel volume/pressure problem. on one of the steel tubes connecting the injectors on either bank of cylinders is a Schrader valve---looks just like a tire valve and works the same way. It's for connecting a test gauge to check for pressure and a hose can also be connected there to check volume. Pressure can be checked after engine has just been shut down, you have to by-pass the fuel pump relay for valume test. I'm not sure about your chassis, for years Ford used two pumps, one low pressure pump mounted in-tank to transfer fuel to a frame mounted high pressure pump. You might want to check that out to see if you've got this system.What with the large volume of fuel returned to the tank by the fuel pressure regulator, vapor lock is very seldom encountered any more. Ford did have trouble with their regulators, but that was a ruptured diaphragm which allowed copious amounts of gasoline to be sucked into the intake manifold via the vacuum hose attached to the regulator.
I did attach a fuel pressure gage to the manifold thats how i know the pressure is dropping its also not dropping off all at once most of the time its when you put a small load such as going over an overpass while traveling on a flat highway if I contine on then the pressure and speed drops off slowly I don't think that the electrical supply to the fuel pump is going and returning I didn't find a booster pump like ford is putting on thier new cars now.
OK, it's got only the single high pressure pump in the tank. Since you have a pressure gauge and know how to use it, hook it up to the test valve, start engine and run for 5 minutes at idle, record pressure. Remove vacuum hose from top of fuel pressure regulator( it's right on the fuel rail,(tubing),pressure should jump to 40-45Lb PSI if pump pressure and regulator are good. Come back with what you find.
kent ,at idle the pressure reads about 28 to 30 .when I first turn on the key it jumps to about 38 then the relay clicks it drops to 30 when Istart the engine it drops to @26 then when i do like you said it goes to around 45 I have run it down the road while monoriting the pressure 20 miles later the pressure drops to 24 to 25 maybe a bad regulator will let you know as soon as get it replaced tommorrow thanks for the help so far .I was going to restrict bypass but I think I might cause other problems so I'm replacing the reg first.
as usual a dealer stock item ordered maybe monday will let you know.
OK, will be looking for your post. The sequence of events you describe are caused by the following Turn key on, pressure jumps to around 38 PSI--that's because when the key is turned to run position pump relay is turned on for 2 seconds to prime system, then relay opens and leaves pressure in system for starting. After engine starts, intake manifold vacuum is applied to regulator--this "tailors" fuel pressure to engine load, higher engine load= lower manifold vacuum=higher fuel pressure in fuel rails.With engine running, pinching off the vacuum allows full pump pressure in the rails. If you wanted to check for sure if it is the regulator and not the pump, splice in enough vacuum hose so you can bring it up to the driver's seat, go for a ride, and when the trouble develops, pull the vacuum hose open---that's so you don't "trap" vacuum in the regulator--and see if engine power returns. That way, you'll know for sure it's the regulator and not the pump/ electrical feed.
98 pace arrow /4 fuel pumps later losing fuel pressure after sometimes 50 miles then other times 300 miles is not vapor locking because just as soon as you pull off and shut down engine it will start back up wait an hour it will go maybe another 50 to whenever it decides to start bogging down again. have changed fuel filters hoping for bad fuel not helped except for cool down time
Bearing in mind that 90% of fuel problems are ignition problems, the first thing is to determine if you do, indeed have a fuel volume/pressure problem. on one of the steel tubes connecting the injectors on either bank of cylinders is a Schrader valve---looks just like a tire valve and works the same way. It's for connecting a test gauge to check for pressure and a hose can also be connected there to check volume. Pressure can be checked after engine has just been shut down, you have to by-pass the fuel pump relay for valume test. I'm not sure about your chassis, for years Ford used two pumps, one low pressure pump mounted in-tank to transfer fuel to a frame mounted high pressure pump. You might want to check that out to see if you've got this system.What with the large volume of fuel returned to the tank by the fuel pressure regulator, vapor lock is very seldom encountered any more. Ford did have trouble with their regulators, but that was a ruptured diaphragm which allowed copious amounts of gasoline to be sucked into the intake manifold via the vacuum hose attached to the regulator.
I did attach a fuel pressure gage to the manifold thats how i know the pressure is dropping its also not dropping off all at once most of the time its when you put a small load such as going over an overpass while traveling on a flat highway if I contine on then the pressure and speed drops off slowly I don't think that the electrical supply to the fuel pump is going and returning I didn't find a booster pump like ford is putting on thier new cars now.
OK, it's got only the single high pressure pump in the tank. Since you have a pressure gauge and know how to use it, hook it up to the test valve, start engine and run for 5 minutes at idle, record pressure. Remove vacuum hose from top of fuel pressure regulator( it's right on the fuel rail,(tubing),pressure should jump to 40-45Lb PSI if pump pressure and regulator are good. Come back with what you find.
kent ,at idle the pressure reads about 28 to 30 .when I first turn on the key it jumps to about 38 then the relay clicks it drops to 30 when Istart the engine it drops to @26 then when i do like you said it goes to around 45 I have run it down the road while monoriting the pressure 20 miles later the pressure drops to 24 to 25 maybe a bad regulator will let you know as soon as get it replaced tommorrow thanks for the help so far .I was going to restrict bypass but I think I might cause other problems so I'm replacing the reg first.
as usual a dealer stock item ordered maybe monday will let you know.
OK, will be looking for your post. The sequence of events you describe are caused by the following Turn key on, pressure jumps to around 38 PSI--that's because when the key is turned to run position pump relay is turned on for 2 seconds to prime system, then relay opens and leaves pressure in system for starting. After engine starts, intake manifold vacuum is applied to regulator--this "tailors" fuel pressure to engine load, higher engine load= lower manifold vacuum=higher fuel pressure in fuel rails.With engine running, pinching off the vacuum allows full pump pressure in the rails. If you wanted to check for sure if it is the regulator and not the pump, splice in enough vacuum hose so you can bring it up to the driver's seat, go for a ride, and when the trouble develops, pull the vacuum hose open---that's so you don't "trap" vacuum in the regulator--and see if engine power returns. That way, you'll know for sure it's the regulator and not the pump/ electrical feed.
kent replaced reg. now pulling hills pressure goes up .I believe the reg was bad thanks for the help you were a great help and if i can repay the favor please let me know thanks again
charles
98 pace arrow /4 fuel pumps later losing fuel pressure after sometimes 50 miles then other times 300 miles is not vapor locking because just as soon as you pull off and shut down engine it will start back up wait an hour it will go maybe another 50 to whenever it decides to start bogging down again. have changed fuel filters hoping for bad fuel not helped except for cool down time
Bearing in mind that 90% of fuel problems are ignition problems, the first thing is to determine if you do, indeed have a fuel volume/pressure problem. on one of the steel tubes connecting the injectors on either bank of cylinders is a Schrader valve---looks just like a tire valve and works the same way. It's for connecting a test gauge to check for pressure and a hose can also be connected there to check volume. Pressure can be checked after engine has just been shut down, you have to by-pass the fuel pump relay for valume test. I'm not sure about your chassis, for years Ford used two pumps, one low pressure pump mounted in-tank to transfer fuel to a frame mounted high pressure pump. You might want to check that out to see if you've got this system.What with the large volume of fuel returned to the tank by the fuel pressure regulator, vapor lock is very seldom encountered any more. Ford did have trouble with their regulators, but that was a ruptured diaphragm which allowed copious amounts of gasoline to be sucked into the intake manifold via the vacuum hose attached to the regulator.
I did attach a fuel pressure gage to the manifold thats how i know the pressure is dropping its also not dropping off all at once most of the time its when you put a small load such as going over an overpass while traveling on a flat highway if I contine on then the pressure and speed drops off slowly I don't think that the electrical supply to the fuel pump is going and returning I didn't find a booster pump like ford is putting on thier new cars now.
OK, it's got only the single high pressure pump in the tank. Since you have a pressure gauge and know how to use it, hook it up to the test valve, start engine and run for 5 minutes at idle, record pressure. Remove vacuum hose from top of fuel pressure regulator( it's right on the fuel rail,(tubing),pressure should jump to 40-45Lb PSI if pump pressure and regulator are good. Come back with what you find.
kent ,at idle the pressure reads about 28 to 30 .when I first turn on the key it jumps to about 38 then the relay clicks it drops to 30 when Istart the engine it drops to @26 then when i do like you said it goes to around 45 I have run it down the road while monoriting the pressure 20 miles later the pressure drops to 24 to 25 maybe a bad regulator will let you know as soon as get it replaced tommorrow thanks for the help so far .I was going to restrict bypass but I think I might cause other problems so I'm replacing the reg first.
as usual a dealer stock item ordered maybe monday will let you know.
OK, will be looking for your post. The sequence of events you describe are caused by the following Turn key on, pressure jumps to around 38 PSI--that's because when the key is turned to run position pump relay is turned on for 2 seconds to prime system, then relay opens and leaves pressure in system for starting. After engine starts, intake manifold vacuum is applied to regulator--this "tailors" fuel pressure to engine load, higher engine load= lower manifold vacuum=higher fuel pressure in fuel rails.With engine running, pinching off the vacuum allows full pump pressure in the rails. If you wanted to check for sure if it is the regulator and not the pump, splice in enough vacuum hose so you can bring it up to the driver's seat, go for a ride, and when the trouble develops, pull the vacuum hose open---that's so you don't "trap" vacuum in the regulator--and see if engine power returns. That way, you'll know for sure it's the regulator and not the pump/ electrical feed.
kent replaced reg. now pulling hills pressure goes up .I believe the reg was bad thanks for the help you were a great help and if i can repay the favor please let me know thanks again
charles
kent I Thought You had me taken care of but problem returned after three hours straight driving replaced fuel relay nope,I have found out though that all I have to do which I know is bad is let off gas put in neutral shut off key start again put in drive and magic all the power I need if i run it to 90mph ok untill it decides to slow down again sometimes 100 miles other 30 to 50 have sent off for wiring diagrams and schematis for this chasis and engine trying to find out what controles fuel pump/relay and learn as much as I can .Next will put idiot lights to monitor all power to pump through all associated devices
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