93 MarkVIII Gen I
Hi,
I haven't visited here in a while. My Mark sat for about a week and would not start, the tank was near empty last time I drove it and my rear bags had deflated (bad sensor?) sometime during that week so the car was on a slight incline. Car cranks and cranks continuously but will not start. Put the battery charger on the battery and is on low amp charger. I am assuming fuel is the problem. Here is what I have done so far with my observations and where I am at the moment.
1) Filled tank with 8 gallons of gas
2) Checked for gas at the shrader like valve on the drivers side fuel rail by by releasing it with a small phillips head while my daughter cranked the motor. No gas at that port.
3) Removed the fuel line at the incoming/lower side of the fuel filter. A few ounces of gas drained out of the filter. Cranked motor several times no fuel coming from the open fuel line.
At this point I am assuming something is wrong with the fuel pump. There is a fuel cut off switch on the drivers side in the trunk. The red button on this switch was depressed. It is described as an inertia switch. It has two pk/blk wires running into it. I assumed the depressed red button was the "off" position so I popped it up with a screwdriver. I tried cranking the motor again but still no fuel. I read on the other forum about a Fuel delivery module and the cutoff switch, etc. The FDPM (?) I can't seem to find! On the passenger side in the trunk there is a well insulated black exterior line that has a connector with red and pk/blk inputs. The black exterior line runs through a large rubber grommet and I assume this is the line that powers the fuel pump.
I am going to do the following
1) swap fuel relay in main fuse box and test (crank motor)
2) have my daughter turn the ignition to run to see if I can hear the fuel pump coming on or off (sound ?)
With the ignition on I get 4.8V at the red lead wire connector coming from the wiring harness when it is grounded to chassis. I also get 4.8 V when i put black wire from the voltmeter to the pk/blk wire in the connector. the pk/blk wire from that connector has connectivity (ohm meter near zero) to one of the pk/blk wires of the fuel cutoff switch.
I thought I could test whether or not the fuel pump was working by adding 12V to it somehow but I don't understand the wiring system or electrical stuff well enough to know how the switch(es) works(?). Don't want to damage anything in the wiring system w/o understanding what I am doing! I would appreciate any ones thoughts and diagnosis with the information I have provided...Have not looked at a wiring diagram for the fuel system. At any rate comments help would be appreciated!
Thanks!
Hi,
I haven't visited here in a while. My Mark sat for about a week and would not start, the tank was near empty last time I drove it and my rear bags had deflated (bad sensor?) sometime during that week so the car was on a slight incline. Car cranks and cranks continuously but will not start. Put the battery charger on the battery and is on low amp charger. I am assuming fuel is the problem. Here is what I have done so far with my observations and where I am at the moment.
1) Filled tank with 8 gallons of gas
2) Checked for gas at the shrader like valve on the drivers side fuel rail by by releasing it with a small phillips head while my daughter cranked the motor. No gas at that port.
3) Removed the fuel line at the incoming/lower side of the fuel filter. A few ounces of gas drained out of the filter. Cranked motor several times no fuel coming from the open fuel line.
At this point I am assuming something is wrong with the fuel pump. There is a fuel cut off switch on the drivers side in the trunk. The red button on this switch was depressed. It is described as an inertia switch. It has two pk/blk wires running into it. I assumed the depressed red button was the "off" position so I popped it up with a screwdriver. I tried cranking the motor again but still no fuel. I read on the other forum about a Fuel delivery module and the cutoff switch, etc. The FDPM (?) I can't seem to find! On the passenger side in the trunk there is a well insulated black exterior line that has a connector with red and pk/blk inputs. The black exterior line runs through a large rubber grommet and I assume this is the line that powers the fuel pump.
I am going to do the following
1) swap fuel relay in main fuse box and test (crank motor)
2) have my daughter turn the ignition to run to see if I can hear the fuel pump coming on or off (sound ?)
With the ignition on I get 4.8V at the red lead wire connector coming from the wiring harness when it is grounded to chassis. I also get 4.8 V when i put black wire from the voltmeter to the pk/blk wire in the connector. the pk/blk wire from that connector has connectivity (ohm meter near zero) to one of the pk/blk wires of the fuel cutoff switch.
I thought I could test whether or not the fuel pump was working by adding 12V to it somehow but I don't understand the wiring system or electrical stuff well enough to know how the switch(es) works(?). Don't want to damage anything in the wiring system w/o understanding what I am doing! I would appreciate any ones thoughts and diagnosis with the information I have provided...Have not looked at a wiring diagram for the fuel system. At any rate comments help would be appreciated!
Thanks!
