question about mileage during first several minutes of driving a direct injection engine

Agree, If the buying public was ok with buying lower powered vehicles, fuel economy could rise tremendously. My old 2001 Honda Civic gets high 30s mpg because it is small, light and has a tiny 1.7 116hp engine. But the markets have spoken. People want bigger, faster, and more gluttonous vehicles.
Not me. I like my small car, if I tried to drive an SUV the way I do my car, I'd flip it over.
 
To the OP: The engine runs rich and open loop until certain parameters within the OBDII requirements are met at which point it switches to closed loop operation and at its most efficient settings.

 
Curious as to what brand and oil spec you are you running?
I have used QSUD and RGT, both Ford spec 5w-30, 946-b1 and 961-a1. I am just reading the replies now and thank you all for sharing this information; these details are much better than a "that's how these engines are" answer.
 
I believe engines run rich when warming up to get up to operational temp quickly and to heat the catalytic converts up to operational temp quickly.

Using more fuel to fire the cat creates more pollution (exhaust) volumetrically , impossible to do otherwise.

Especially for those driving short trips the ECU should always try for best economy to reduce pollution and the supply side pollution .
Current EPA tune doubles pollution for short trippers and causes more engine wear.

Our perverse desire to reduce a single pollutant NOx has meant we allow all other pollutants to go out of control CO2, CO, VOC, sulphur compounds all rise
all because of a fear of a small increase in the percentage of NOx which in most areas of the country is a non-issue.

Should not measure “percentages” during warmup and focus on reducing how much exhaust is emitted.
 
People that are smart with their money don't buy a $75k+ depreciating asset. They buy a $30k depreciating asset and invest the difference.

No matter what, a vehicle loses value over time, collectors excluded.
VTI, not so much.....
Or they buy a $4000 fixer upper that will always be worth more than what they paid……and invest the rest. :)
 
people that are smart with their money buy full size trucks because they hold their value better than anything else. go priced a used truck vs a used car and get back to me.
I like compact trucks or full sized trucks ,,I just like them.
 
People that are smart with their money don't buy a $75k+ depreciating asset. They buy a $30k depreciating asset and invest the difference.

No matter what, a vehicle loses value over time, collectors excluded.
VTI, not so much.....
I bought a new 2015 2.7 super cab dealer stock XL with some options for a hair under $35,00000 . out the door and a 2018 F350 XL X cab dealer stock 6.2 gas engine with a few options form $41,500.00 out the door . Being able to afford a purchase goes beyond bein able to make the monthly payments.
 
Hello, I drive a 2020 F-150 with a 2.7l engine. It has both port and direct injection and if I understand correctly it starts and initially runs on the direct injections primarily/only during the first several minutes of driving. I make several 15 minute trips a week and I notice that for the first 5 minutes or so the 5-minute-mileage history and instantaneous mileage shows a very low number, maybe 12 mpg and then hops up to the mid-20s for the rest of the drive. My trip (tank) mileage will drop .1 mpg for the first several minutes then come back to where it was for the rest of the drive. Driving conditions are the same throughout the drive, only the engine/transmission temp is obviously colder initially, currently about 50F. Additionally, the engine seems to have a slightly uneven idle when I start it, perhaps like a slight misfire, occasionally. One little "putt" every few sections in an otherwise smooth sound.

I am wondering if the things I notice are related and if there is anything that can/should be done. My mileage would be quite a bit better, I think, if 1/3 of the time I was driving I wasn't getting less than 15 mpg, when all the driving is the same. Could my engine be running too rich for some reason? Interested in insights-

Thanks
Any engine during its warm up period of operation will consume more gas as mentioned . The gasoline doesn't vaporize in a cold engine as it does in a warm engine and other mechanical reasons.
 
Using more fuel to fire the cat creates more pollution (exhaust) volumetrically , impossible to do otherwise.

Especially for those driving short trips the ECU should always try for best economy to reduce pollution and the supply side pollution .
Current EPA tune doubles pollution for short trippers and causes more engine wear.

Our perverse desire to reduce a single pollutant NOx has meant we allow all other pollutants to go out of control CO2, CO, VOC, sulphur compounds all rise
all because of a fear of a small increase in the percentage of NOx which in most areas of the country is a non-issue.

Should not measure “percentages” during warmup and focus on reducing how much exhaust is emitted.
Aside from changing the oil earlier than usual and perhaps using a brand that is on the higher side of viscosity for the grade, is there anything to be done to prevent wear? I assume you are referring to fuel dilution relate wear.
 
I assume you are referring to fuel dilution relate wear.

it depends on the car, but yes fuel dilution is one , many “diesel “ problems with short tripping didn’t exist in the 1980’s 100% emissions related in that case our TDI would even plug the turbo which we had to clean out almost once a year in some cases.


If it’s a Gen III Prius it’s far worse as it messes up the egr, fouls sensors and eventually causes a blown head gasket.

The high reliability of a Gen II Prius was eliminated by a small uptick in the level of required pollution controls .


Although the CAT and sensors are usually cleanable on other cars short tripping now is more likely to plug the cat than historically and if that happens you are normally told to replace it instead of “burning it out “with a torch
 
People that are smart with their money don't buy a $75k+ depreciating asset. They buy a $30k depreciating asset and invest the difference.

No matter what, a vehicle loses value over time, collectors excluded.
VTI, not so much.....
and you can get a truck for 30k. always jump to the most obscene example to make a point. emotional argument and not facts.
 
Aside from changing the oil earlier than usual and perhaps using a brand that is on the higher side of viscosity for the grade, is there anything to be done to prevent wear? I assume you are referring to fuel dilution relate wear.
Don't worry about it , just enjoy the vehicle.
 
and you can get a truck for 30k. always jump to the most obscene example to make a point. emotional argument and not facts.
Great and a reliable used car can be had for $4k if you're willing to invest some DIY work into it. We can all find extremes and exceptions to the focus of the discussion.

It still doesn't change the fact that any daily driven vehicle is a depreciating asset. People who are smart with their money will minimize their investments in depreciating assets and maximize their investments in appreciating assets.

Nothing emotional about that.

Long story short, a truck is not a good place to stick your money and lots of people who are very smart with their money would do the opposite of what you claim.
 
Great and a reliable used car can be had for $4k if you're willing to invest some DIY work into it. We can all find extremes and exceptions to the focus of the discussion.

It still doesn't change the fact that any daily driven vehicle is a depreciating asset. People who are smart with their money will minimize their investments in depreciating assets and maximize their investments in appreciating assets.

Nothing emotional about that.

Long story short, a truck is not a good place to stick your money and lots of people who are very smart with their money would do the opposite of what you claim.
i was operating under the assumption of buying a new vehicle and so was original response so instead of debating the original topic you change the scenario. the original comment was 30k vs 70k i pointed out that fallacy and you had to change to some 4k junk to try to make a point. A truck will hold its value better and be more reliable over the long haul. sorry these are facts. get used to it.
 
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i was operating under the assumption of buying a new vehicle and so was original response so instead of debating the original topic you change the scenario. the original comment was 30k vs 70k i pointed out that fallacy and you had to change to some 4k junk to try to make a point. A truck will hold its value better and be more reliable over the long haul. sorry these are facts. get used to it.
A depreciating asset depreciates.
An appreciating asset appreciates.

If you're smart with your money, you put it in an appreciating asset, not a truck because a truck loses value.

I can't make it more simple than that.

Cheers!!!
 
A depreciating asset depreciates.
An appreciating asset appreciates.

If you're smart with your money, you put it in an appreciating asset, not a truck because a truck loses value.

I can't make it more simple than that.

Cheers!!!
everyone with a brain stem understands that, but you have to buy a vehicle to get anywhere. so you may as well buy something that losses as little as possible.
 
everyone with a brain stem understands that, but you have to buy a vehicle to get anywhere. so you may as well buy something that losses as little as possible.
When the price delta between a full sized pickup and a compact car is $30k, then the fact that the truck depreciates slower is both true and irrelevant. You're still investing that extra $30k in a depreciating asset. That's not smart money. Smart money goes into appreciating assets like VTI.

If you need that truck for it's capabilities, that's one thing, but this discussion has been only about financial decisions.

Here's the 2021 data on new car purchase prices. Lo and behold, $52,800 for a full sized pickup, $22,400 for a compact car.

Repeat after me, a depreciating asset isn't where smart money puts their cash......
 
When the price delta between a full sized pickup and a compact car is $30k, then the fact that the truck depreciates slower is both true and irrelevant. You're still investing that extra $30k in a depreciating asset. That's not smart money. Smart money goes into appreciating assets like VTI.

If you need that truck for it's capabilities, that's one thing, but this discussion has been only about financial decisions.

Here's the 2021 data on new car purchase prices. Lo and behold, $52,800 for a full sized pickup, $22,400 for a compact car.

Repeat after me, a depreciating asset isn't where smart money puts their cash......
repeat after me that is the average sales price. you can get a truck for 30k. you're speaking in circles because you don't have a leg to stand on.
 
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