my paseo has a similar problem. started out as a small tick, but only when i really steped on the gas. In about a week i noticed a louder tick w/ another gurgling sound(almost souded like an exhaust leak) but i didnt hear it wen i was coasting. finally one day on my way to the shop it broke into all out schreaching. wen i popped the hood it was obvious the ticking was coming from one of the belts, so i bought some belt dressing and sprayed them, and it stopped. Of course come to find out, it is. Getting it fixed first thing tommorow all belts replaced including timing belt for $100, not bad. Im no mechanic tho, just a suggestion