I have a 2007 FEH with a little over 7000 miles and for the past few days my FEH has not been able to go to just EC when I'm idle i.e. stopped at a light or just parked with the engine on. I'm assuming it's probably a software glitch. At first I thought it was just going through the battery charging phase but then I noticed my car will not go under 1000 rpm's even when I'm just sitting at a stop light or coasting down hill. It will go into EC mode at high coasting speeds but not at slow speeds like 15mph and under, which in the past it would do without problem. Has anyone ever run into this problem and if so how was it corrected. Since it's under warrenty I'll be taking it to the dealer, but I was just wondering if this was a rare or common occurance.

 

Where do you live? How cold is it there?

It was extremely cold here this morning, and my ICE would not turn off for more than a few seconds. Even once I got to work, the ICE would not turn off when I was in the parking deck (first time it ever did not turn off there).

 

If its cold its likely there is nothing wrong with your vehicle. The engine wont go into EV if the temperature is very cold until it has been on for a pretty LONG time. This is done both to keep the catalytic converter hot and probably to reduce the number of times a COLD engine is restarted. Warm restarts are less strain.

I live in MI and under 20 I have to drive pretty far to get the engine to drop into EV mode at all... on top of that with the greater cooling and the cold battery not being able to provide as much current it doesn't stay there very long at all.

 

When the ICE on my FEH will not shut down due to over battery or generator heating or if it's to cold to except regen by the double tap or "L", I shift to to neutral and tap the brakes two or three times. Normally I shut down the ICE before I come to a stop and prefer to glide from 40mph in EV. Regen will sometimes prevent EV, so if you shift to "N", there is no regen to stop EV from happening.

GaryG

 

I thought if you were in "N" the engine would not be allowed to shut off because the controller realizes it can't restart the engine to keep it warm, so the engine would stay in idle. Apparently I understood wrong?

 

Tim, that's only if your speed is less than 6mph. It's called passive neutral, and the engine must remain in the state it was (running or not running) when the mode was entered and is not permitted to change state (start or stop). You can shift to "N" above 6mph and stay in active neutral till you stop. If you folks don't use this feature, your missing a good technique to shut down the ICE. If you shift to neutral above 6mph, say at 65mph, you can do a FAS (key-off) glide and start back up in "N" at any point. I don't do it, but I may start if conditions for safety are present. I did it yesterday while my ICE was cold and knew I had to stop for a long train ahead. It worked great and I just restarted the ICE after the train cleared.

GaryG

 

I'm curious. If you are deliberately shutting the engine down and letting it get cold, does that not increase overall emissions? A cold catalitic converter won't work well which is why the engine goes on once and a while to keep it hot. It would be good to know how long a hot idling engine needs to work to equal one cold start.

When you are gliding with the key (engine) off, do the steering and braking systems still work?

Regards,

rcomeau

 

I don't think temperature is an issue in my instance since I live in Los Angeles. After I take in to the shop I'll post the issue and hopefully solution on this tread.

 

This prob not your problem, but pretty dumb (I'm guilty): I once had defrost on, and all the way home complaining there there must be something wrong with my car since the ICE never shuts down

 

Hi rcomeau

My situation is a little different in that 30F is about as cold as it gets here, and I could count those days with one hand for the entire winter. The CAT gets hot enough (~600F) within a mile from my house with a cold morning start. This is the point where the engine goes closed loop and emissions are better than 50% burned.

Anytime the engine is shut off for EV or key-off, fuel injectors are shut off first, and the remaining fuel is burned while air and spark continue to clean the manifold of unburned fuel through the cylinders in the FEH. This takes less than a second.

The CAT gets to ~1,200F (Max) real fast and retains its heat far longer than any FAS (forced auto stop), even while waiting for a long train. You people who live in severe cold weather? In a max FAS (unless your going down a mountain), about 3 min, its not long enough for the CAT to cool down enough to worry about emission when you restart. After all, you go that long all the time in EV.

During a key-off FAS, the brakes work the same, but you loose power steering (which saves battery), which is no big deal unless you do alot of turning. You wouldn't do a key-off FAS in that kind of situation. If I had to turn fast, its not that hard anyway. If you do a key-off high speed FAS (over 40mph where you can't just go EV), I turn the key back in the on position right away so the SG and the Navi continue your MPG averages.

Like I said, I rarely would need to do a key-off FAS because my mileage is still very good going EV at 40mph. Waiting to to go EV at 40mph allows regen thoughout gliding down where key-off has no regen unless you key-on start again. You also can't take off in EV after a key-off FAS.

Situations like I had where I saw train rails coming down a quarter mile away and the ICE was to cold for EV, key-off allowed a glide to a stop and prevented sitting still during a warm-up with the ICE running. There will be other times I may take advantage of a key-off FAS glide in neutral, but you must have a rare situation where a key restart is better for FE than going EV at 40mph and "N" gliding.

The real point I was making was using the brake taps in neutral when the ICE will not go EV in "D" or "L". I do this every day all the time and I go EV anytime I try. When Wayne Gerdes was diving my FEH last year, I showed him how it works.

GaryG