I have 98 coupe ex with a gsr swap and b16 tranny p28 chipped ecu. The problem I am having is that I go threw a full tank of gas in like 3-4 days I drive about 30-50miles daily mainly hwy 60% 40% I try not to pass 4k on the rpms on the hwy because of the short gears. My question is shouldn't I be getting more than 200 miles per gallon? Also when I let off the gas and I rest my foot on the gas petal it makes a popping sound that I hear through the exhaust, could that be a reason why I'm burning so much gas.

 

I'm also pumping 93 octane

 

Get us an actual and exact mileage number, and we can work with you. Reset your trip meter the next time you fill your gas tank. Drive normally. When you go to fill up again, divide your trip meter reading by the number of gallons you added at the second fill up.

Also, you don't need to run 93 on a stock B16C1.

Third, when was your last full tuneup? Air/oil filters, oil change, cap, rotor, plugs, and wires.

 

I'm gonna fill up today ill do that. Ill fill it with plus this time and see what happenes . Did a tune up about a month ago oem Honda oil filter mobileone 10w-30 hp synthetic ngk wires and plugs the car has a new dizzy.

 

ECU staying in cold loop maybe.

 

What do you mean by cold loop? The ecu isn't throwing any cels

 

These are obvious but check tire pressure and air filter as well. Where does the idl sit at normal operating temp?

 

It idles around 800 but everyone and then it will fluctuate 800-900 the car has a one month dc sports intake new Dunlop tires too.

 

What kind of tune or basemap do you have?

 

New dizzy doesn't mean new cap or rotor. Pull them and check for hot spots. Like someone else said, air filter should be replaced as well. Let us know when you have a real number.

 

If your engine coolant temp isn't getting up to normal operating range or the sensors are not reporting the normal operating range the ECU will continue to run as if the engine is cold providing a richer mixure and wasting fuel. This won't necessarily throw a code.
The O2 sensors could also be faulty causing a similar condition.
Does the car roll freely? Do you have to apply more than normal throttle to get normal performance?

 

*wastes



(Sorry, OP ... I usually let spelling mistakes slide (like breaks vs. brakes) but this one just got to me.)

 

how do u know your cel light even works does it come on for a few seconds when u turn the key on and unless u bump the timing up u dont need to run 93 gas maybe 89 at the highest

 

x2

 

My car doesn't have o2 sensors could that be a problem? The engine harness is an auto obd2 With a obd1 jumper. It car runs fine. Except sometimes when I pop v for example in 2nd gear then shift to third and drive regular the car feels as if its jerking as I accelerate but the rpms don't fluctuate.

 

I have no idea the guy I bought it from told me he had it dyno tuned. But idk about that.

 

Yes my check engine light does work it comes on when I put the key forward and when I do the diagnostic thing the cel only stays on to day I filled up with 89 octane so lets see what happens.

 

All these posts and nobody touches on the fact you have the b16 tranny with short gears.
Changing out 5th gear and using a taller LS 5th gear will help bring the rpms down at freeway speeds.
Lower rpm=less gas used.
This made a drastic difference in my fuel milage when I did this to my B18B LS powered EG.
Look into it.

 

How much does swapping the fifth gear run? Is it a lot of work? Is it a job that can be done on my own like I can easily drop the tranny alone in like an hour. I did have that in mind but I'm scared of doing it myself if anything I'd have a shop do that when I get my LSD installed.

 

i have the Same problem with my car ( VTI D16Y8 1997 Sedan - Automatic Gearbox ) and its original without any tuning...

can any one help..

Note : 20 L gas 90 Octane goes for 120Km only

 

I have a 1998 EX manual too, no swaps, a D16Y8.

Does you fuel gauge rise or fall while cornering or incline/declines?
The fuel tanks aren't baffled and causes this as well as inaccurate readings.
I thought mine was getting poor gas mileage too during the first few months after I purchased it (7 months ago). I got new wires,cap,rotor,and plugs but didn't help.

3 months ago I decided to see just how far I could run the gas gauge down below the red (empty) line. I carried around a 1 gallon gas can as soon as the gauge was level with the red line. Not to surprisingly I drove another 70 miles before it stalled and the gauge needle was clearly below the red line.

Please now, everyone dry your tears I am really not a hero. Although I put my fuel pump in jeopardy for this forum and it's quest for knowledge. Just knowing that I may have helped solve one of thousands of civic questions, gives me great joy and content.

 

Take your car to a professional tuner. I can almost guarantee your problem will go away.
If not, try your luck with another basemap. Get it from Xenocron or phearable.net here on HT.

 

It is killing me every time I see it on the page.

 

I doubt this is the problem because the car has an 11.9 gallon tank and I usually pump around 10-11 gallons every time I doubt ill get 70 miles out of a gallon

 

My tank lasted 238 miles before my gas light came on I filled up this time with regular 11.2 gallons so let's see how long this lasts I think my coil is bad on my dizzy the car really backfired a lot when I let off