Hello all,
I am having an issue that seems common to FJ60s, the random sputtering issue. Mine is a 1987 FJ60 completely stock with the original US emissions. The DUI distributor is one of the few things that is not stock. After a thorough search of related issues in the tech forums, I discovered that the issue I'm experiencing may overlap with many things. This has been a long journey down a rabbit hole replacing parts, scratching my head, and not going anywhere. I need help.
First the issue- between 1200-2200 RPM the engine seems to sputter. This goes away under load somewhat. I started to experience this about a year ago. About three years prior to that I replaced my stock distributor with a DUI. The problem is very intermittent. One day it is running like a top and then the next it is a herky-jerky ride. Two times I have blown and replaced the control modules in the DUI distributor. I just replaced the entire DUI with another after trying to diagnose the problem and hearing a buzzing electrical noise from around or inside the DUI. This happened after the ground was disconnected. I am guessing that a capacitor in the DUI was keeping things energized. Maybe something was grounding out inside the DUI?
I should also mention these things to alleviate other symptoms:
-The carburetor was recently rebuilt, the fuel is fresh, and is treated with ethanol treatment. I put Startron into it at every fill up.
- The fuel pump is good. It is delivering fuel at idle and under load.
- All fuel filters are replaced with new.
-The intake gasket was replaced.
- The vehicle was smoke-checked for vacuum leaks. There were none.
- Before the first control module blew, the timing would retard under load. I checked the adavance on the DUI replaced the control module with a new one and the symptoms stopped. This seemed to narrow the issue to the DUI... or so I thought.
- The timing is set to stock for an FJ60.
- The plug wires have continuity. I have not checked resistance.
- EGR seems to be working, i.e. not plugged but without replacing it I am 100% sure it is good. Frankly I am tired of replacing parts.
After reading many of the fixes in the forums, I have discovered two more possibilities. One is the tachometer causing this. Maybe it is grounding or shorting out? Do I replace or try to refurbish it? The other is the emission control computer. I am not sure if I should replace it (again, another part replacement) or maybe just disconnect it. Then again I just don't know what is happening. I took it to my club mechanic and even he gave up after going down the same rabbit hole of part replacing and guessing. Any help that you can provide is appreciated. I am tired of this Alice in Wonderland adventure. Thanks.
I am having an issue that seems common to FJ60s, the random sputtering issue. Mine is a 1987 FJ60 completely stock with the original US emissions. The DUI distributor is one of the few things that is not stock. After a thorough search of related issues in the tech forums, I discovered that the issue I'm experiencing may overlap with many things. This has been a long journey down a rabbit hole replacing parts, scratching my head, and not going anywhere. I need help.
First the issue- between 1200-2200 RPM the engine seems to sputter. This goes away under load somewhat. I started to experience this about a year ago. About three years prior to that I replaced my stock distributor with a DUI. The problem is very intermittent. One day it is running like a top and then the next it is a herky-jerky ride. Two times I have blown and replaced the control modules in the DUI distributor. I just replaced the entire DUI with another after trying to diagnose the problem and hearing a buzzing electrical noise from around or inside the DUI. This happened after the ground was disconnected. I am guessing that a capacitor in the DUI was keeping things energized. Maybe something was grounding out inside the DUI?
I should also mention these things to alleviate other symptoms:
-The carburetor was recently rebuilt, the fuel is fresh, and is treated with ethanol treatment. I put Startron into it at every fill up.
- The fuel pump is good. It is delivering fuel at idle and under load.
- All fuel filters are replaced with new.
-The intake gasket was replaced.
- The vehicle was smoke-checked for vacuum leaks. There were none.
- Before the first control module blew, the timing would retard under load. I checked the adavance on the DUI replaced the control module with a new one and the symptoms stopped. This seemed to narrow the issue to the DUI... or so I thought.
- The timing is set to stock for an FJ60.
- The plug wires have continuity. I have not checked resistance.
- EGR seems to be working, i.e. not plugged but without replacing it I am 100% sure it is good. Frankly I am tired of replacing parts.
After reading many of the fixes in the forums, I have discovered two more possibilities. One is the tachometer causing this. Maybe it is grounding or shorting out? Do I replace or try to refurbish it? The other is the emission control computer. I am not sure if I should replace it (again, another part replacement) or maybe just disconnect it. Then again I just don't know what is happening. I took it to my club mechanic and even he gave up after going down the same rabbit hole of part replacing and guessing. Any help that you can provide is appreciated. I am tired of this Alice in Wonderland adventure. Thanks.