Hi I have a 2004 chevrolet classic automatic. When I slow down at a stop light my car acts like it is going to shut off on me. I notice a humming sound right before it starts trying to shut off. And when I take off I here a clunk sound. It does not happen every time I am driving but it been happening more often lately. Could someone help me out?
I recommend that you have a mechanic perform an inspection. You could have a number of issues that can cause this drivability concern. Some items may be such as; IAC ( Idle Air Control Valve), Alternator windings failing, Mass Air Flow Sensor....The list can go on with possibilities. I recommend visiting a reputable mechanic.
Hope this helps!
A. J. Valle
Hi, the humming noise could be associated with extreme heat (engine blowing out). More importantly, I would have a mechanic look at the sensors and valves related to the vehicle's Idle Air Control. The referenced "clunk" sound could be a transmission mount. If you are hearing it while you turn the wheel as well it could be a control arm though it is most likely just the former.
〉 Answered on Aug 30th, 2011 by Kerri Papajohn, Marketing Director at USA Sealants, Inc.
This may be a transmission issue. I would try to get your trusted technician to try to duplicate the scenario so they can get a good idea of everything that is happening. Make sure they test drive it and not just make a guess based on what you have experienced!
〉 Answered on Aug 30th, 2011 by Judy Curry, Co-Founder and Vice President of Marketing at Currys Auto Service