- Joined
- May 18, 2025
- Messages
- 4
- Points
- 1
- City
- Port Angeles, WA
- Vehicle Year
- 1992
- Transmission
- Automatic
I’ve had this issue on a 1992 Ranger 4.0L OHV 4x4 I recently purchased from an auction site.
Main symptom besides the fuel pump continuously running with KOEO is that once I get it running by spraying carb cleaner in the air intake is that it runs super rich. Idles fine, under load it will sputter and die unless I feather the accelerator.
Of course I replaced the commensurate amount of engine sensors related to air/fuel mixture a person who doesn’t know what they are doing is required to do in order to find a solution, but to no avail.
After much research, even though I had a newish Mexican ECM rebuild from RockAuto I decided to have the ECM rebuilt by Keyworks in Richmond, VA (he has a YouTube channel). He replaced a few capacitors. The issue stopped for about a week. I emailed him and he said he stands behind his work and I could return it so he could verify his repairs, I said hold on as I wanted to dink around with it first.
while checking for shorts in the engine bay I decided to pull the fuse going to the fuel pump relay. The engine ran for another 10 seconds or so, then I put the fuse back in and the problem disappeared.
it’s been running fine all day, no engine codes, no problems accelerating. I expect the problem to return, but at least I know how to kick start it now.
Does anyone with electrical know-how think they know what the ultimate solution might be?
Main symptom besides the fuel pump continuously running with KOEO is that once I get it running by spraying carb cleaner in the air intake is that it runs super rich. Idles fine, under load it will sputter and die unless I feather the accelerator.
Of course I replaced the commensurate amount of engine sensors related to air/fuel mixture a person who doesn’t know what they are doing is required to do in order to find a solution, but to no avail.
After much research, even though I had a newish Mexican ECM rebuild from RockAuto I decided to have the ECM rebuilt by Keyworks in Richmond, VA (he has a YouTube channel). He replaced a few capacitors. The issue stopped for about a week. I emailed him and he said he stands behind his work and I could return it so he could verify his repairs, I said hold on as I wanted to dink around with it first.
while checking for shorts in the engine bay I decided to pull the fuse going to the fuel pump relay. The engine ran for another 10 seconds or so, then I put the fuse back in and the problem disappeared.
it’s been running fine all day, no engine codes, no problems accelerating. I expect the problem to return, but at least I know how to kick start it now.
Does anyone with electrical know-how think they know what the ultimate solution might be?
