1 Too rich to start, too lean to rev Sun Feb 19, 2023 2:36 pm
swampyankee
active member
Still not havin success getting my 86 K100RS project to run right.
To date I've replaced injectors, plugs, reconnected the wires to the temp sensor and bought a new battery. After trying in vain to start it (over and over again), yhe new plugs seemed to help immensely and it was starting from cold at the touch of the button. After warming up though, it would not start uless i unplugged the fuel pump. Today i changed out some very fuel-laden oil and when I tried to start it I had to resort to unplugging the fuel pump right from cold. Even then, it would not idle and revved roughly, coughing and spurting. I checked and cleaned the plugs which were pretty black. I fiddled with the idle air mixes and idle speed and finally got it to idle ok, but still not revving smoothly. I found that it ran better with the fuel regulator vacuum line off and port plugged. I tried hitting the starter button at idle and it stalled, yet at just off idle it would rev when the starter button was pressed. I drew vacuum on the line going to the fuel regulator and its leak free. I even pulled the air box to make sure the line hadn't been pinched the last time I had the airbox off and all was good. After getting flakey "hot" ohm readings, I have a new temp sensor on order but after today I'm not so sure that will do anything for me, especially since it wouldn't even start cold.
This situation is getting very discouraging. I'm about to sell it and buy something with carburettors!
To date I've replaced injectors, plugs, reconnected the wires to the temp sensor and bought a new battery. After trying in vain to start it (over and over again), yhe new plugs seemed to help immensely and it was starting from cold at the touch of the button. After warming up though, it would not start uless i unplugged the fuel pump. Today i changed out some very fuel-laden oil and when I tried to start it I had to resort to unplugging the fuel pump right from cold. Even then, it would not idle and revved roughly, coughing and spurting. I checked and cleaned the plugs which were pretty black. I fiddled with the idle air mixes and idle speed and finally got it to idle ok, but still not revving smoothly. I found that it ran better with the fuel regulator vacuum line off and port plugged. I tried hitting the starter button at idle and it stalled, yet at just off idle it would rev when the starter button was pressed. I drew vacuum on the line going to the fuel regulator and its leak free. I even pulled the air box to make sure the line hadn't been pinched the last time I had the airbox off and all was good. After getting flakey "hot" ohm readings, I have a new temp sensor on order but after today I'm not so sure that will do anything for me, especially since it wouldn't even start cold.
This situation is getting very discouraging. I'm about to sell it and buy something with carburettors!