Little nuances

I've noticed there are times when accelerating from a full stop, the MFD will show about 6-9 mpg until I hit ~20mph. During this time, the engine really sounds like it's straining and the acceleration isn't as responsive. I know that decent acceleration usually shows about .5 mpg/mph, but this seems a little unusual. The ambient temperature will be anywhere from 30-70 when I've seen this happen.

There will be other times when I can accelerate purely on battery up to about 40mph at a pretty respectable rate of acceleration. This will sometimes even happen about 5 minutes after turning the car on, obviously in warmer weather. I've tried figuring what variables could affect this. I'm not on an incline when the car won't go to battery, the weather is warm, it's several miles since initial startup, etc. All are what would be considered ideal conditions. I guess it would help if I had a Scangauge but I don't want to plunk down that kind of money.

I'll even feather the pedal and the engine/MFD will still sound like it's straining. My MPG for right now is about 51.5 with the temperature hopping around from 40-70, so I'm not really too concerned about the hit on mileage. I'm more curious as to why this is happening because the obvious reasons don't seem to jive (temperature, road, time from start, rate of acceleration, etc).

Any ideas on how to ensure that the car will go primarily to battery from a complete stop other than installing an EV?

 

I've always been told that the goal for acceleration is to achieve .5mpg per 1mph.

 

Why is it the past two tanks I've been getting like 51.5 no matter what. 50 miles into the tank it's 51.5. 200 miles into it I'm at 51.9. The MFD consumption screen since I've been keeping track at 50 miles consistently shows more 5 minute increments of high 50's to 99 and the tank MPG barely moves. Like the first increment will be about 25-35mpg after startup but after that I'm able to hit high 40's/low 50's then the next 5 or 6 are all closer to 60-75 (if I'm not on the highway, that's consistently 50's-60's). Completely different routes, too. I must be really unlucky with my route selection and hitting red lights.

 

So, while the miles on the tank can zero out, my MPG will remain until I reset? Interesting! I used to reset after every fill-up and then stopped last month because it was reseting the miles immediately and I just figured the reset button was redundant. good to know. I must be getting like 54mpg considering I got about mid 51's for 370 miles and I've raised that by 1 MPG now on this tank.

 

Well, I don't know if this was due to Jimbo's advice, but for my last tank I really took extra care to get about .60MPG/MPH while accelerating. I went over 400 miles before going down to 2 pips for the first time ever!

Also, I believe this was more Jimbo advice, but when filling up today, I clicked off after 7 gallons. I pushed my car from side to side several times and sure enough I filled another gallon! After 50 miles on this tank I'm sitting at a cozy 60.7 MPG on the MFD and it was only 55 degrees.

 

Because the engine is sufficiently warmed up slash in s4 before being severely stressed at high speeds? That's my only guess.