My MPG Solved Story

I have a 1997 single cab 4x4 tacoma, I was getting 13mpg, for the life of me I couldnt understand wth was wrong, I changed everything you name it and I tried everything, after doin more research I found somwome say reset ecu by disconnecting battery, I did that and got some 91 gas Chevron, after my odo got 23miles I pulled over and found another Chevron and put 91....... I was crying tears of joy I was getting 23mpg, only took one gallon, idk what did it to fix it but idc Ima get only 91 chevron from now on, i used to get only 87 arco , btw truck is auto, hope this can help anybody having bad mpg again I had a 4banger getting only 13mpg!!

 

Most likely, reseting the ECU cured it, not the Chevron gas. Save your money. Go back to the 87 and you will likely see the same mileage.

 

But stay with the Chevron gas, don't go back to Arco

 

Way to small of a sample drive a tank out then check it

 

What's wrong with the quality of Arco gas?

 

https://www.consumerreports.org/car-maintenance/study-shows-top-tier-gasoline-worth-extra-price/

 

91 octane in a tacoma is a waste of money. You get exactly 0 benefit from it.

 

Unless your engine is designed to use high octane fuel, all gasoline in your area comes from 1 refinery.

 

Exactly. Driving 23 miles then filling back up is essentially meaningless. Just the fact that you used a different pump at a different station could account for a lot of variance in pump shutoff sensitivity. I bet, if you were really seeing 13mpg, that the pump didn’t dispense the full amount you burned.

 

It sure makes a difference in my truck. But then, we have summer/ winter blend fuel in CA.

 

Over a 30 mile trip I've seen 4 mpg and nearly 40 mpg. Not enough distance to be meaningful. I'd suggest 200 miles minimum, and you'd need to take the average of several 200 mile trips to mean anything.

The octane rating has nothing to do with fuel mileage. In some cases it can mean more power for towing. If the engine is tuned for it.

 

No it doesn't. Unless you're running forced induction your engine will do everything it possibly can on 85/87.

 

According to this list about every gas station in town is top tier.

 

Uh... OK.
I guess pinging and advanced timing doesn't mean anything either.

 

He's right. Your engine can run full timing advance with 87. If you are towing 5,000lb uphill for 100 miles, you might get those cylinders hot enough to start pinging on some carbon or something, otherwise waste of money. Timing only advances to a point. You will gain nothing by using higher octane fuel for an N/A 5vz. You only start dealing with pinging with supercharger or turbocharger without fuel mods.

 

Hmmm, then perhaps I should run that octane in my '69 Z/28 Camaro... not.

 

You have mechanical issues if you're detonating while driving.

 

It all depends on your compression ratio. If you have a 9:1 engine and otherwise stock, yeah 87 should be fine. If you hear a little pinging, maybe up the octane rating or check your static timing and timing advance curve.

I can tell you just aren't going to agree, and that's ok. Put whatever fuel makes you comfortable. It isn't that much more in the long run anyway

 

OP,
Great job in finding mpg's.