Hello everybody, i got my micra (K11) a few days back at a bargain price. The seller truthfully confessed that the car will need some TLC and a full service. I drove the car back home without anything going wrong, coolant temperature remained at the norm (despite having a massive hole in the expansion tank and barely any fluid). Today I flushed the cooling system and filled it up with fresh coolant, replaced the thermostat and installed a new expansion tank. While bleeding the coolant system i noticed this weird behaviour...
When the car starts it runs nice and smooth (for its condition), but if i turn the headlights on the engine sound changes and the rpm too. If I turn full beams on then the sound changes further. At first I thought it was the battery or alternator, got my multi-meter out the battery seems ok at 12.4V at the terminals. Checked the alternator and this is where it gets interesting. When the car is idling with all electronics off (stereo, lights, door closed) alternator is pumping out 14.5V peak and average 14.4V. When i get my beams on (dimmed) the alternator drops down slightly to 14.2V, but the engine sound changes (sounds as if it isn't getting enough power, as if it is struggling to keep going). When I get my full beams on with radio plugged in the voltage drops to 14.0V. Now the engine sounds very bad. I decided to turn my emergency lights on just to see what will happen, the sound got very bad so wasn't planning on continuing with this test, but before i went to turn the car off, the voltage dropped from 13.9V to 10V for a fraction of a second twice in a row. I turned off, and went to repeat it this time got 13.9V for about 2-3 minutes that i was running without any drop to 10V.
So my question is, any idea what this might be? The battery I have has a "status" indicator, mine is showing green which means it is functioning normally.
The alternator belt is tight and not in bad condition, bearings are fine too, I will be replacing it when the delivery comes anyway as part of the service.
Finally, when I step on the accelerator a bit in any situation, full beam and emergency or just dimmed regardless, the engine sounds similar and well.
All answers are welcome and thanks in advance.
When the car starts it runs nice and smooth (for its condition), but if i turn the headlights on the engine sound changes and the rpm too. If I turn full beams on then the sound changes further. At first I thought it was the battery or alternator, got my multi-meter out the battery seems ok at 12.4V at the terminals. Checked the alternator and this is where it gets interesting. When the car is idling with all electronics off (stereo, lights, door closed) alternator is pumping out 14.5V peak and average 14.4V. When i get my beams on (dimmed) the alternator drops down slightly to 14.2V, but the engine sound changes (sounds as if it isn't getting enough power, as if it is struggling to keep going). When I get my full beams on with radio plugged in the voltage drops to 14.0V. Now the engine sounds very bad. I decided to turn my emergency lights on just to see what will happen, the sound got very bad so wasn't planning on continuing with this test, but before i went to turn the car off, the voltage dropped from 13.9V to 10V for a fraction of a second twice in a row. I turned off, and went to repeat it this time got 13.9V for about 2-3 minutes that i was running without any drop to 10V.
So my question is, any idea what this might be? The battery I have has a "status" indicator, mine is showing green which means it is functioning normally.
The alternator belt is tight and not in bad condition, bearings are fine too, I will be replacing it when the delivery comes anyway as part of the service.
Finally, when I step on the accelerator a bit in any situation, full beam and emergency or just dimmed regardless, the engine sounds similar and well.
All answers are welcome and thanks in advance.
