So today I left home at 10:30 am with a fully charged battery indicating 28 miles range. Outside Temperature of 75 degrees. A/C off but fan on for ventilation and satellite radio on loud. Drove 14 miles mostly on the freeway with Cruise set to 70 mph. Remaining indicated range of 18 miles. After about 30 minutes drove back home again on Freeway with A/C off and cruise set to 70 mph. Temperature had risen to 81 degrees but still reasonable comfortable. Just as I exited the freeway near my home the indicator dropped to --- but remained on E power. Pulled into the garage at 11:30 am with a total of 27 miles driven on electric power only; ICE never came on. Best I've seen thus far and really pleased was able to drive 70 mph almost the entire way. Some very slight undulations up and down on the roadway but essentially flat most of the way.

My observation is once you get down to about 2 miles of indicated range it quickly drops to the --- indication. I'm guessing this is because it wants/needs to save some power in reserve for spirited driving if needed???

 

I've noticed the same thing regarding the "---" estimated mileage range specification when you get to 2 miles or less of estimated range; seems odd -- like why not show down to 1 mile?
I wrote on the Pan4 E-Hybrid discussion thread earlier today (which I assume you read) that I finally got to 26 or 27 miles of all-electric range going to my office roundtrip by going on all side roads, bypassing the expressway. In my case, I don't think the problem is speed but rather the fact that the expressways here have rather steep hills (ironically), whereas I can find much more level roads driving to and from my office on 2-lane streets and non-highway roads.

I guess I'm one of those unusual Porsche owners who doesn't like my car to sound loud; I didn't get the car to draw attention to myself or my car, but rather to enjoy the pure pleasure of driving a really well-designed and well-built car (and I drive fast, so I like a really stable car at high highway speeds). So I always aim to drive into and out of my residential neighborhood, and at my office/work area, on electric only in this 462-hp car. So I don't often get down to the "---" mark because I'm always aiming to have at least 3-5 estimated range miles on my battery pack when getting within a mile or so of my office and my residential neighborhood.

 

I notice the mileage does drop rather quickly when I'm first getting onto the freeway and accelerating fairly rapidly to merge with the ongoing traffic. Once I set the cruise it usually does fairly well at maintaining or exceeding slightly the actual miles realized vs the remaining indicated. I also usually drive pretty fast and I also don't need/want the engine to be loud and that is why I didn't opt for the Sport Exhaust. Had it actually made a difference in power I would have bought it but to pay $2000 just for more noise made no sense to me personally. In any case, when I really jump on the car it makes plenty of noise and gurgling. Yesterday I was late to a golf tournament and was traveling at 90+ most of the way on the freeway. Fortunately had a couple of other drivers also moving as fast or slightly faster, so I just tagged along with them. This car is everything I'd hoped for and more! It's my fourth Porsche and by far the nicest. Now if I could just get the garage door opener and Amazon Music to work everything would be perfect!!

 

I've heard that Adaptive Cruise Control does help battery drain. I'll try that in Hybrid Auto mode when I'm doing long-distance driving. It doesn't make a lot of sense to use ACC for my commuting because I'm not on any one stretch of road for very long.

Yes, the Panamera 4 E-Hybrid makes lots of exhaust noise without any enhancement. In my neighborhood and work areas, you'd be seen as a dick with loud exhaust if you're not a teenager -- thus the electric stealth mode in those areas. It's actually really amazing to see a Sport Turismo go silently by in electric mode, and even more amazing to drive it that way!

 

Imo, I would not drop tank level on my car to 2miles left or similar.
Always try to fill up at 1/4 left to avoid playing with the crap from bottom of tank. Why wait til last minute, when you can do earlier.
Wife does this on her car - wait til last minute, and something always comes up, and she ends up having to complain that had so little gas.
Fill up = no issues.

 

We are talking about 2 miles left on the electric-battery capacity in our E-Hybrids, not the gas tank!
I usually fill up the gas tank when it gets to between 1/4 and 1/3 full.