i just recently bought a nissan murano, still under warranty its a 2004, i noticed that when i take my foot off the gas and just coasting, it seems normal at first but when it decreases to 20kms/h it seems like the the engine brakes come on. and at that moment if i touch the gas it seems like it slams forward a little. not sure if something is seased up or if it's just normal.. any ideas?