Engine Starts and Stops when at Standstill

[Gregavi]

Hi all,

I have a 2013 Fusion Hybrid that I have had since late 2014. Recently I have noticed that when I am stopped (Red Light, Drive Through at 'In and Out' etc.) my car's gas engine will start and then go off and back on about every 5 seconds. This will go on indefinitely until I start to drive again. Also, it seems that my gas mileage has been going down pretty dramatically over the past 1 to 2 years. I'm not sure exactly how much the decrease has been because I only recently started documenting my gas mileage about 2 or 3 months ago. In that time I have been getting around 28 MPG. I do know that for the first 3 to 3-1/2 years, when I filled up, the "Miles To Empty" (MTE) would be in the 550-590 range. It began to drop about 1-1/2 years ago and was down to the mid 300s until I replaced my 12V car battery. That apparently re-set the computer and it appears that it went back to the factory setting because after replacing the battery and did my first fill up, the MTE read 585. Could it be that the hybrid batteries are starting to fail? I asked the Local Ford dealer about warranty on the hybrid batteries and they told me that they are only under warranty if they fail completely. Any insight appreciated. Thanks in advance.

[Texasota]

Was it cold with your HVAC heater on? Going through a drive through with your window down could cool your interior down fast requiring the ICE to start to generate cabin heat. Just a thought...

[Gregavi]

Was it cold with your HVAC heater on? Going through a drive through with your window down could cool your interior down fast requiring the ICE to start to generate cabin heat. Just a thought...

That's definitely not the issue but thanks for the reply. This has happened many times in all kinds of conditions, including varying weather conditions. (As much as we have varying weather conditions in Santa Barbara)

[lolder]

Starting and stopping every few seconds is not normal.