Looks like it's time for another problem. Since the last time I posted with a problem here, I had the rear left wheel bearing replaced, and the headlight leveling system reported an error but then somehow fixed itself :)
Now there's another problem. From about 20 km/h there's a weird, pulsating noise coming from somewhere which is probably the loudest at around 30km/h, but then quickly disappears as I accelerate. It's hard to describe, as I said it's pulsating, as if something was grinding only at a particular spot during rotation. The noise appears to be dependent on road speed and not engine speed, as I can let it drop to ~1k RPM when going downhill or coasting to a stop.
I tried to record the sound with my phone, so hopefully it's good enough to hear what's going on.
Download the mp3 here. From a complete stop I slowly get up to about 25-30 km/h and stay there for a bit (from about 8-10 seconds), then accelerate to about 70 just to see that the noise isn't there. You can also heart it at the very end when I slow down into a turn. The noise isn't necessarily as loud or as quiet as it might sound, as I messed with the volume in a sound editor.
To me this sounds nothing like how the bearing did, although I didn't get to try the usual tests (sharp turns, etc). There are also some quite ticking noises at the beginning, but I suspect that's just the key chain banging on something. The car is a 2001 Caravan 2.2 automatic, with about 145k km. So, any suggestions what might be causing this, or what can I do to try to find out? Thanks.
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Topic: Strange pulsating noise at low speed (Read 530 times)