Is the set screw still in place at the base of the distributor? Even if it was loose, I don't think the dissy could change timing enough to stall the motor. However, that's something I've never tried.
91 fj80 wont start no power to fuel pump (1 Viewer)
- Thread starter kingslender
- Start date
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- Thread starter
- #22
Is there a proper way to disconnect the air flow meter connector to test it? I have seen posts where people have said they have screwed the AFM up trying to disconnect it. Just wondering if thats for the connector or the AFM itself
DO NOT REMOVE THE SCREWS.
There is a thin spring clip that must be raised on either side of the plug and then it just comes right off.
There is a thin spring clip that must be raised on either side of the plug and then it just comes right off.
- Thread starter
- #24
Thanks for the tip Jon,
The set screw was still in the Dissy, even moved it a little each direction and tried to start with no change. The AFM tested good per ohm specs. I removed the ignition control module to have that tested on the advice of a friend but no auto place has the connectors to test it. Any tips on how to test it at home?
Also pulled the distributor cap off and the top and the dissy was pretty corroded under the cap.
So in review,
Cel is working now. (It is on all the time with key in on position, no codes flashing)
Fuel pump will only turn on when jumping the Fp and B+ pins.
There is spark at spark plugs
When fuel pump is jumped there is fuel getting to cylinders ( wet plugs )
The truck will crank but will not start.
parts replaced or tested good
Ignition coil
Plug wires
Plugs
Distributor cap
Rotor button
Efi relay
Cor
Fusible links
Fuel pump
AFM
Cel bulb
Is there any hope for this thing to ever run again....?
The set screw was still in the Dissy, even moved it a little each direction and tried to start with no change. The AFM tested good per ohm specs. I removed the ignition control module to have that tested on the advice of a friend but no auto place has the connectors to test it. Any tips on how to test it at home?
Also pulled the distributor cap off and the top and the dissy was pretty corroded under the cap.
So in review,
Cel is working now. (It is on all the time with key in on position, no codes flashing)
Fuel pump will only turn on when jumping the Fp and B+ pins.
There is spark at spark plugs
When fuel pump is jumped there is fuel getting to cylinders ( wet plugs )
The truck will crank but will not start.
parts replaced or tested good
Ignition coil
Plug wires
Plugs
Distributor cap
Rotor button
Efi relay
Cor
Fusible links
Fuel pump
AFM
Cel bulb
Is there any hope for this thing to ever run again....?
What part is the "ignition control module"?
You said that you replaced the cap and rotor and now you say that there was corrosion under the cap. Are you using new OEM parts?
So you have spark and fuel and compression and the motor won't fire? I think you don't have 1 of those things. If you had all 3 this motor would run.
The ECU doesn't control the fuel pump. It runs while cranking the starter and once the motor catches it runs from the flap in the AFM. Even if you disconnect the AFM, the motor would catch while cranking and die once you released the starter.
Did you check the COR?
Did you check the fuel rail for pressure?
How old it the inline fuel filter? If it's clogged with poop you'll be getting a trickle of fuel to the injectors.
You said that you replaced the cap and rotor and now you say that there was corrosion under the cap. Are you using new OEM parts?
So you have spark and fuel and compression and the motor won't fire? I think you don't have 1 of those things. If you had all 3 this motor would run.
The ECU doesn't control the fuel pump. It runs while cranking the starter and once the motor catches it runs from the flap in the AFM. Even if you disconnect the AFM, the motor would catch while cranking and die once you released the starter.
Did you check the COR?
Did you check the fuel rail for pressure?
How old it the inline fuel filter? If it's clogged with poop you'll be getting a trickle of fuel to the injectors.
- Thread starter
- #26
The cap and button are not oem. I looked for other posts on how to check the Cor, any advice? Im sure the fuel filter is old, will change it out, and I need to check the fuel rail pressure.
Please read post #13 and post #17.
I'm having a similar issue right now but I've confirmed that I'm not getting any spark to the fuel pump. Can someone make a video or include pictures of how to jump the FP and B+ on the PS firewall?
I’m new to the ih8mud community and new owner of a 1994 rig- that has very similar issues described here. I have limited mech experience but have been looking for a LC a project for quite a while.
Curious if any resolution was found. I bought it as non running and so far a new battery has gotten me to the point of the original poster.
Planning on working thru the fuel pump first, relays as described, plugs, needs to have valve cover gasket replaced as well.
There will be a lot more but trying to get it to run first. It ran until @14 months ago. PO couldn’t get it to start, put in new battery and still wouldn’t run. There’s a parasitic battery drain present as yet undiagnosed.
I do have a video but not sure how to post it yet.
Thanks for any feedback
Todd
Did anyone every figure out how to resolve this or where else to look? I’m having the same issue. All the relays have been checked/replaced, fuel pump is getting 12V when jumping the DLC but without jumping it the fuel pump isn’t getting any power. Any ideas or help would be greatly appreciated!
Resolved?
Please keep in mind that there are differences in fuel pump logic between the 91/92 3FE, the OBD1 1FZ-FE, and the OBD2 1FZ-FE. Without knowing what engine you're discussing, there's no way to properly diagnose.
