In Brief
In my 2008 Ford Escape Hybrid, the car will occasionally jump to a noticeable decrease in power and display a "Stop Safely Now" message. I have to restart the car to resolve. But how can I trace to the root cause? Is it truly my hybrid battery or is it something else?
Details
First and foremost, yes I read this earlier post on a Ford Escape Hybrid having a "stop safely now" message. In that post, they did a lot of (good!) work and traced the problem down to a dirty throttle body assembly. I've checked my throttle body and it looks clean (and I sprayed it anyway). The problem persists.
The problem looks like this:
- At times (probably 1x or 2x per week) I will be driving the car, and suddenly I can feel a sudden loss in drive power -- the car still goes, but there is a very noticeable and very sudden deceleration of the car. The dashboard beeps and displays a message saying "STOP SAFELY NOW". I can actually drive the car for a little bit after that happens, though drive power is certainly weaker than it could be.
- To get things back to normal, I need to pull over and turn the ignition off and re-start the car. Typically I only need to do this once, but sometimes I need to try more than once.
- Almost always, this problem occurs when I've just started the car and started driving -- like within the first 100 yards or so.
A lot of online resources say the problem is most likely the hybrid battery. But there are other potential root causes too. So right now, it looks like the recommended approach to fixing this problem is "spend a few thousand dollars to replace the hybrid battery, that might work. And if that doesn't work, then try something else..."
Is there any way for me to do better than that? Is there any way for me to verify if the problem is truly the hybrid battery? Or the throttle body? Or the electric motor cooling pump? Or something else?
(I have plenty more details and will be happy them if they help, but as a starting point I figured this post was already long enough so I won't bore people with more details unless they ask.)