gas mileage and RPM

[mitsubishiv5]

try a transmission flush, and find out if the torque converter is faulty or possible transmission solenoid is bad

[Shadow1]

try a transmission flush, and find out if the torque converter is faulty or possible transmission solenoid is bad

Honda transmissions arent made to be flushed. it actually messes some, if not all of them, up. drain and refill is his best bet. try checking your tune up stuff. i know when i did a tune up and fresh oil change on my 2nd CB, i was sitting at 220 miles BEFORE i got to the half way mark.

[emosun]

i'll get some specific readings asap

ok got em

at 60 / 2700

at 65 / 3000

at 70 / 3250

at 75 / 3400

at 80 / 3600

[Bad_dude]

ok got em

at 60 / 2700

at 65 / 3000

at 70 / 3250

at 75 / 3400

at 80 / 3600

I have a 1990 Accord LX 4AT sedan. It's at 70/with 3000rpm. It definitely does not give over 400 miles to the tank. I would say around 320 miles to the tank. I rarely ever let it goes to empty. Usually refill the tank at the latest a quarter left.
How could I set my timing to improve this gas mileage? I have done the ignition last year so it didn't change from the original timing when I got the car. I marked it. I did the valve lash adjustments and clean the EGR ports and valve as well. It drives smooth and shift good. I have change the trans.fluid 2 twice within 2000 miles and I used Honda's ATF.

Thanks.

[Bad_dude]

Just check my timing again. That red mark is so hard to see. The car seems to drive smooth and all. I wonder what is killing my gas mileage? I don't drive like a maniac. I wonder if that gas gauge is inaccurate? I never ran it to totally empty so I don't know.

[wed3k]

ive gotten 450 on a tank but it was all flat land. that gas light will fluctuate when there's different inclination angles.

[islandhopper]

90' DX Coupe 5-Speed Manual Transmission

75MPH@~3300RPM

w/Mixed Driving: 450+miles to the tank depending on how heavy my foot gets.

w/All Highway Driving: 500+miles on one tank. Steady cruising at ~75-80mph.

[Bad_dude]

Wow, you guys got really good mileage.
I have changed the rotor/cap/cables. All are NGK except for rotor. Timing is good. Oil change synthetic, trans fluid just done. No brake drags. Well maintained and no leak. Coolant is done as well. EGR cleaned. Air filter is good. Good tire pressure. Drive gently. Valve lash adjusted. Mixed local and freeway driving and I still get around 24mpg or less.
What else could I do guys to help with my gas mileage? I am unemployed, I cannot manage $40 per week fill up.

Thanks.

[spectre]

I only get a little over 500km (310miles) per tank, with an automatic and F22A6 It's 90% city driving though.

[Bad_dude]

I only get a little over 500km (310miles) per tank, with an automatic and F22A6 It's 90% city driving though.

That's about where my car would be.

[Fleetw00d]

I'm sorry, but I wish you guys would post actual mileage calculations based on miles traveled diviided by gallons of fuel you actually put into the tank. There is so much variability in "per tank", it doesn't mean a whole lot. My wife usually only puts in 12-13 gallons at a fill. I'll usually push them to about 14, so our "per tank" mileage will be different.

I've put almost 4,000 miles on my EX in the last 5 weeks. All number below are purely highway:
34+ mpg at 65 mph max no A/C
31-32 mpg at 65 mph max with AC
30 mpg at 70 mph max with AC
28 mpg at 73-74 mph max with AC

[islandhopper]

13.67 gallons/430.5 miles=~31.5mpg mixed driving.

[deevergote]

I'm sorry, but I wish you guys would post actually mileage calculations based on miles traveled diviided by gallons of fuel you actually put into the tank. There is so much variability is "per tank", it doesn't mean a whole lot. My wife usually only puts in 12-13 gallons at a fill. I'll usually push them to about 14, so our "per tank" mileage will be different.

I've put almost 4,000 miles on my EX in the last 5 weeks. All number below are purely highway:
34+ mpg at 65 mph max no A/C
31-32 mpg at 65 mph max with AC
30 mpg at 70 mph max with AC
28 mpg at 73-74 mph max with AC

I haven't driven my car in 3 years, so "per tank" is about all I can offer. I always fill up shortly after the gas light comes on.

Regardless, these cars are so old, and most are in various states of modification and repair... combined with different atmospheric conditions based on weather and altitude... one person's results will vary drastically from another's.

[emosun]

Reguardless of my climate or altitude , barely 300 to any cb7 tank is bad.

Can anyone with an auto confirm my rpm's I posted are correct?

Also is the torque converter hard to fix/replace?

[psawall]

Your situation of oddly high RPM in the 60-70mpg range is one that is very similar to what I experienced when my speed sensor was out. Without the speed sensory working, my car would shift fine, but when on the highway I noticed the torque converter would not lockup, and my RPMs were probably identical to what you are experiencing now. So with that said, step one would be to identify if your TC is locking up. How to do it? Just count the gears as you get on the highway, and after you get into the 50-55mph area (maybe higher) you should notice another slight drop in RPM, almost like it's shifting into 5th. That final RPM drop is the TC "locking up" or spinning at a 1:1 ratio with the crank shaft. If you don’t see that last drop in RPMs, it’s not locking up. From my experience, if your TC does not lock up, it doesn’t mean you have a bad TC. You’re more likely to either have an issue of a faulty/sticky solenoid or faulty TCU not sending the signal to the lockup solenoid (or bad wiring in between).

The lockup solenoid is very easy to find, if you’re standing in front of the car and looking at the tranny you’ll see what looks like a pair of size C cell batteries sticking up, and there will be a wire connecting to the device. If you unplug the wire from the harness and measure the resistance between each of the leads going to the solenoid and ground (NOT resistance between pins 1 and 2), each one should measure between 14-16 ohms. If resistance is not in spec, replace it. If it’s okay, take a wire from the positive battery terminal and connect it to each of the solenoid leads, one at a time. You should hear a clicking sound. If not, you probably need to replace. If it works, you might want to remove the solenoid(s) and check the small filter screens underneath to see if they are clogged.

That’s where I’d start, and then get back to us. Replacing torque converter means dropping the transmission so it’s not easy. Good luck.