Worst MPG for a 1.5L civic

[Neen]

This is more of a general question but I thought we would set a pretty common engine as the base test model.
So we know we can squeeze out ridiculous numbers out of many different engines. What I was wondering is how <i>poor</i> can fuel economy get without bogging and killing an engine. Let's assume a good chassis and no external fuel leaks. No unnatural drivetrain losses. Just straight up poor fuel metering and bad A/F mixtures running super rich

I'm thinking EPA numbers can be cut 60% at most.

[SentraSE-R]

I'm sure it's possible to get low teens with an old carburetor-fed 1.5 driven like you stole it.

[drmiller100]

my son is 16. He gets up, drives 4 miles to the first school.
car sits for 2 hours.
then he drives 2 miles to the next school. car sits for 2 hours.
then he goes to lunch - 2 miles including the drive through with his buddies. car sits for 2 hours.
then he comes home.

then he goes and gets a movie at the gas station, ice cream, store, whatever.

on his odometer he goes right at 280 miles in two weeks, and puts right at 7 gallons of gas in.

That is a 93 hatchback with a 5 speed. I think I could get it down to 30 if I tried, but I'd get a ticket or two if I did it for a full 7 gallons of gas.

[Neen]

Does anyone know what the A/F mixture has to be at the maximum rich value in order to have combustion?

[brucepick]

Why???

[Christ]

I've actually gotten sub 20's in a DPFI 1.5L Civic. Like 18MPG, all stock. Takes almost constant acceleration at WOT, though.

[Neen]

Originally Posted by brucepick

Why???

Because i like physics...I'm curious if it would be even possible to dump double the fuel into the combustion chamber and have combustion. Plus it's information that we can use to help diagnose fuel consumption issues. If someone is saying that they are getting 15 mpg out of a 1.5L we can maybe isolate it down to a fuel leak verse poor fuel consumption.

[euromodder]

Originally Posted by drmiller100

my son is 16. He gets up, drives 4 miles to the first school.
then he drives 2 miles to the next school.
then he goes to lunch - 2 miles

At 16 I used my bike , which was all I was allowed to ride .
(we can only get a car licence at 18)

[niky]

Toyota sold a van here in Asia that was notorious for being a gas guzzler. We called it the Revo, but the more common name is the Kijang. Just 2 liters, but it went down to 10 mpg in city traffic at times (without idling for hours at the stoplight). When the shop fitted it with an LPG kit, they dyno'd the thing. Imagine our shock when this fuel-injected, two-liter four-banger showed AFRs of 10:1... at idle.

Thus, when the LPG kit was tuned, it saw a 30-40% fuel economy increase instead of the typical 10% decrease.

Worst case AFRs I have seen from stock gasoline vehicles are in the 9-10:1 range. Any lower and you'll be spewing fuel droplets out the tailpipe.

[JQmile]

I got 11mpg with a 5.0 Mustang doing burnouts at every stop light/sign and then 21mpg coasting everywhere. It's a V8, but I would think the same theory applies.