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- canada
- Vehicle Year
- 1994
- Make / Model
- Ford
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- Manual
Yes, 50/50 test just to make sure spark is working AND..........sparking at the right time
You can manually turn on the fuel pump relay on OBD1 vehicles
You need to find the OBD1 connector in the engine bay, in 1987 it should be on passenger side of the engine bay between fuse box and firewall on the main wiring harness to the computer in the cab, it may have a cap on it that says "EEC"
Look here for OBD1 plug slots: https://www.therangerstation.com/tech_library/OBD_I.shtml
Fuel Pump slot is labelled
This slot is connected to computer pin 22 and the Ground for the Fuel Pump Relay, the computer grounds the fuel pump relay to activate it with Key on, but only for 2 seconds, its a safety thing
So you can use a jumper wire in that slot to Ground the fuel pump relay full time
Ground a jumper wire
Turn on the key
Put jumper wire in that slot, you should hear fuel pump relay "click" if its working, and you should hear the fuel pump come on if its working
You can try to start the engine, IF you hear the fuel pump running
If it starts and runs then try pulling out the jumper, if engine runs for a few seconds and stalls then YES, you may have a computer problem
But put the jumper back and restart, then go for a drive and see if there are any other engine issues
If there is no "click" of fuel pump relay with key ON and Jumper in place:
You can also use a volt meter and test that same slot for 12volts with key on, it should show 12v because fuel pump relay gets 12v with key on, so you are seeing voltage passing thru the fuel pump relays coil
If no 12v then EEC relay or its wire to fuel pump relay is bad
The fuel pump power is from a fusible link connected to starter relays(solenoid) battery positive post
There will be a few fusible links on that one post, that post is the Power Distribution Point for the whole vehicle
So if fuel pump doesn't come on when fuel pump relay is activated then either the pump is bad or fusible link is blown
When you have the Ground jumper in place, and Fuel pump relay "clicks", use volt meter at the inertia switch to test if there is 12volts from the fusible link
Overall its more likely you would burn out fuses and fusible links than damage the computer by bad battery "jumping"
You can also damage alternator's voltage regulator
So once you do get engine running you should test for that
You can manually turn on the fuel pump relay on OBD1 vehicles
You need to find the OBD1 connector in the engine bay, in 1987 it should be on passenger side of the engine bay between fuse box and firewall on the main wiring harness to the computer in the cab, it may have a cap on it that says "EEC"
Look here for OBD1 plug slots: https://www.therangerstation.com/tech_library/OBD_I.shtml
Fuel Pump slot is labelled
This slot is connected to computer pin 22 and the Ground for the Fuel Pump Relay, the computer grounds the fuel pump relay to activate it with Key on, but only for 2 seconds, its a safety thing
So you can use a jumper wire in that slot to Ground the fuel pump relay full time
Ground a jumper wire
Turn on the key
Put jumper wire in that slot, you should hear fuel pump relay "click" if its working, and you should hear the fuel pump come on if its working
You can try to start the engine, IF you hear the fuel pump running
If it starts and runs then try pulling out the jumper, if engine runs for a few seconds and stalls then YES, you may have a computer problem
But put the jumper back and restart, then go for a drive and see if there are any other engine issues
If there is no "click" of fuel pump relay with key ON and Jumper in place:
You can also use a volt meter and test that same slot for 12volts with key on, it should show 12v because fuel pump relay gets 12v with key on, so you are seeing voltage passing thru the fuel pump relays coil
If no 12v then EEC relay or its wire to fuel pump relay is bad
The fuel pump power is from a fusible link connected to starter relays(solenoid) battery positive post
There will be a few fusible links on that one post, that post is the Power Distribution Point for the whole vehicle
So if fuel pump doesn't come on when fuel pump relay is activated then either the pump is bad or fusible link is blown
When you have the Ground jumper in place, and Fuel pump relay "clicks", use volt meter at the inertia switch to test if there is 12volts from the fusible link
Overall its more likely you would burn out fuses and fusible links than damage the computer by bad battery "jumping"
You can also damage alternator's voltage regulator
So once you do get engine running you should test for that
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