Marineman7777
Recruit
- Joined
- Sep 24, 2016
- Messages
- 5
I have a 2000 Cobalt 252 with the engine described in the title. I've had it about a year.
Symptoms: all cylinders appear to be running a little lean - light brown on all spark plugs, idles smooth, strong acceleration and has full power, I notice vibration starting about 1100 rpm until about 1600 rpm then much less noticeable the higher the rpm. The vibration is not intense but it is clearly noticeable.
What has been done thus far: Thought is was the outdrive so took it to a Volvo Penta dealer and they completely inspected the outdrive and shafts and all was good but this had no effect on the vibration. I replaced all the spark plugs with no effect. I did not notice any single plug that would indicate misfire (all light brown). Checked for fault codes and there were none logged. From previous threads, I thought the fuel cell may be causing the problem so I removed and cleaned the fuel cell. I found a few particles in the pump screens but not very much. I reinstalled and checked the fuel pressures - 41 psi high and 11 psi low...seems ok (no effect on vibration). Removed the distributor cap and found some corrosion...cleaned it up and the engine ran smoother and the rpm vibration band got smaller. I seem to be onto something that makes a difference. Do you think the next step is to replace the distributor? Suggested tests to do next?
Symptoms: all cylinders appear to be running a little lean - light brown on all spark plugs, idles smooth, strong acceleration and has full power, I notice vibration starting about 1100 rpm until about 1600 rpm then much less noticeable the higher the rpm. The vibration is not intense but it is clearly noticeable.
What has been done thus far: Thought is was the outdrive so took it to a Volvo Penta dealer and they completely inspected the outdrive and shafts and all was good but this had no effect on the vibration. I replaced all the spark plugs with no effect. I did not notice any single plug that would indicate misfire (all light brown). Checked for fault codes and there were none logged. From previous threads, I thought the fuel cell may be causing the problem so I removed and cleaned the fuel cell. I found a few particles in the pump screens but not very much. I reinstalled and checked the fuel pressures - 41 psi high and 11 psi low...seems ok (no effect on vibration). Removed the distributor cap and found some corrosion...cleaned it up and the engine ran smoother and the rpm vibration band got smaller. I seem to be onto something that makes a difference. Do you think the next step is to replace the distributor? Suggested tests to do next?