Worst MPG for a 1.5L civic

[LeanBurn]

Anything is possible...just because it is a small engine doesn't mean it can't guzzle:

http://www.youtube.com/watch?v=badoMjA_rW0

[joat09]

http://www.youtube.com/watch?v=4PsNAqhw5jw

Pretty sure this would get about the worst gas mileage you could get out of one.

[Neen]

So it's looking like 9:1 is the worst AF mixture you can have without flooding. With that being said does that translate straight into fuel consumption? In other words if ideal (stock) is for the most part 14.7:1 would a 9:1 A/F mixture be using 38% more fuel at any given time? Let's assume normal operation and look strictly at A/F ratios and not driving styles.

If the decrease in A/F ratio is more or less translated into fuel consumption then it looks like the worst fuel consumption in any given scenario is roughly 38%. Anything beyond that and it would have to be a fuel leak at that point. Does this sound correct?

[Christ]

You'd have to figure the A/F ratio across RPM and appoximate VE to have any sort of an accurate figure.

9:1 at idle is a heck of a lot less fuel than 9:1 at 4,500 RPM @ WOT.

[user removed]

How about 1.5 liter at 2 MPG.

regards
Mech

[SentraSE-R]

Enough speculation & WAGs. Here's a 1998 DX averaging 14.2 mpg, and another 1998 averaging 19.4 mpg. Just to show those two aren't quirks (they're only 3 tanks apiece), here's a South African who's only averaging 16.9 mpg over 1650 recent miles in a 1999 Civic.

[hamsterpower]

I don't mean to sound sexist but many of us with wives can answer the driving style part with the same car as an example. My wife consistently gets 24 mpg tank after tank in her 99 Integra auto. I drove her car on a 75 mile each way trip last year and averaged 47 MPG (per SGII) mixed highway and highway stop and go traffic. (no engine off coasting) note: I did anger other drivers by leaving more than 3 feet between me and the car infront.

[Neen]

Originally Posted by Christ

You'd have to figure the A/F ratio across RPM and appoximate VE to have any sort of an accurate figure.

9:1 at idle is a heck of a lot less fuel than 9:1 at 4,500 RPM @ WOT.

Yep I get that...but the difference between 9:1 and 14:1 should be constant at any given RPM or load condition correct? Such as 9:1 at 4500rpm at WOT is ~140% of the fuel consumption of 14:1 at 4500rpm at WOT right?

If someone came to this forum and was like; "I used to get 30 mpg now I'm getting 15 mpg. I'm driving the same and I don't see any leaking fuel, do you think my plug wires need replacing?"
We can say, "Hold up man/woman...chances are you have an external fuel leak that you are not detecting cause your engine wouldn't even run if you doubled the fuel amount into the cylinders. You better start at the tank and move forward looking for a leak."

So I was wondering if A/F ratio on average would translate directly into fuel consumption with all other variables being constant...I'm guessing it does. This will help me troubleshoot my own cars in the future...thanks for the feedback!

[Christ]

In that case, yes.

[drmiller100]

I'm a mechanic. I get cars in all the time with drivability issues.

First question: Is the check engine light on?
Second question" What do you get for MPG?

the first can be a bunch fo stupid stuff which won't affect mileage, or it can be a BIG problem which really messes it up.

The second gives a hint. From there, the scan gauge, possibly a ride around the block with the customer driving, and I can usually figure out what is wrong