I've noticed when I reset the ECU, I lose fuel ecomony. On the 3 tank full after reseting the ECU, I'll get very good gas millage. So, reseting the ecu doesn't work for me.

 

You have to have a good reason for resetting the ECU because when you do this, it goes back to the factory default settings. And what does this engine do when it's new? It runs extra rich, thus, you're observed fuel economy. It takes a while for it to "learn" that it doesn't need to be quite that rich.

 

[QUOTE]Originally posted by xviper
[B]
You have to have a good reason for resetting the ECU because when you do this, it goes back to the factory default settings.

 

[QUOTE]Originally posted by xviper
[B]
You have to have a good reason for resetting the ECU because when you do this, it goes back to the factory default settings.

 

so what does this all mean? It should be safe to say that reseting the ecu for purposes other than getting rid of CEL is a waste, no?

 

You are most likely correct as I don't have such info. But this would explain vapors2k's mileage situation as I wouldn't think he drove the car the way you would on a dyno for whole tankfuls of gas. (ie, He's driving it at part throttle most of the time,)

 

[QUOTE]Originally posted by xviper
[B]
You are most likely correct as I don't have such info.

 

I got 299 miles out of 1 tank, and ~220 out of maybe 10 tanks, but I have gotten only 175 miles out of most of my tanks. I drive my car like a road warrior most of the time, and I rarely get on the highway. Basically, I haven't been able to notice any long term trends for fuel economy.

I am NOT saying that there is nothing to be gained from resetting the ECU. I AM saying that there is nothing to be lost, in terms of power at WOT, from resetting the ECU. Actually, if the weather is hot, and you get some marginal gas that causes some detonation, the ECU will retard timing for quite a while. I have done some psuedo-scientific "tests" with a buddy of mine (TypeSH) that has ALWAYS shown some difference between a learned ECU and a reset one.

TypeSH has an '02 S2000 that is almost identical to mine. Whenever one of us makes any sort of change, we do "comparative" drives. We will meet at a spot halfway between our homes that has very little traffic with U-turns at each end. We will get side by side at around 25 MPH in 3rd gear and synchronize before a "1-2-3-go". We will do this around 10 times before deciding that we have resolved it. His backup fuse is always out, but I don't usually reset my ECU until we have had a few runs. My car has done at least as well, or better, with a reset ECU.

I believe that constantly resetting the ECU has only 1 significant downside, and that is the unstable idle (and possibly poor fuel economy). I consider it to be about like the Hondata intake gasket, which doesn't really GAIN power, it just prevents some LOSS of power.

 

xviper, which continent do you live on?

 

Not that literal, old boy!
"American" NOT as in domestic, NOT as in North America. But as in U.S. of America as opposed to Canadian (where we have DRL's).