I want to get a mazda5(2010) through hertz rent2buy program. I tried out two cars. Both have issues with RPM sometimes bouncing between 500 and 1000 from a cold start(put in idle). Initially, I thought that there could be a leak somewhere which usually causes this bouncing RPM. But, after test driving two cars, two cars have the same symptom. I start wandering if this is a "feature" to this 2010 Mazda5. Thank you.